diff --git a/assets/components/openshift-router/deployment.yaml b/assets/components/openshift-router/deployment.yaml
index af1f48f67f..cb2c7b5f31 100644
--- a/assets/components/openshift-router/deployment.yaml
+++ b/assets/components/openshift-router/deployment.yaml
@@ -58,6 +58,8 @@ spec:
               value: '{{ .ThreadCount }}'
             - name: SSL_MIN_VERSION
               value: '{{ .RouterSSLMinVersion }}'
+            - name: ROUTER_CURVES
+              value: '{{ .RouterTLSCurves }}'
             - name: ROUTER_USE_PROXY_PROTOCOL
               value: "false"
             - name: GRACEFUL_SHUTDOWN_DELAY
diff --git a/pkg/components/controllers.go b/pkg/components/controllers.go
index e9bdf7af50..fdde5b9c6b 100644
--- a/pkg/components/controllers.go
+++ b/pkg/components/controllers.go
@@ -27,6 +27,9 @@ const (
 	haproxyMaxTimeoutMilliseconds = 2147483647 * time.Millisecond
 )
 
+// isFIPSEnabled reports whether the cluster has FIPS enabled.
+var isFIPSEnabled = detectFIPS()
+
 var (
 	tlsVersion13Ciphers = sets.NewString(
 		"TLS_AES_128_GCM_SHA256",
@@ -35,8 +38,41 @@ var (
 		"TLS_AES_128_CCM_SHA256",
 		"TLS_AES_128_CCM_8_SHA256",
 	)
+
+	fipsApprovedTLS13Ciphers = sets.NewString(
+		"TLS_AES_128_GCM_SHA256",
+		"TLS_AES_256_GCM_SHA384",
+	)
 )
 
+// detectFIPS reports whether the cluster is operating in FIPS
+// mode by checking the FIPS_ENABLED environment variable if set or
+// the /proc/sys/crypto/fips_enabled file otherwise.
+func detectFIPS() bool {
+	if v, ok := os.LookupEnv("FIPS_ENABLED"); ok {
+		if result, err := strconv.ParseBool(v); err != nil {
+			klog.Warningf("Failed to parse FIPS_ENABLED environment variable: %v; falling back to procfs", err)
+		} else {
+			klog.Infof("Found FIPS_ENABLED environment variable: value=%s, result=%v", v, result)
+			return result
+		}
+	}
+
+	result := false
+	data, err := os.ReadFile("/proc/sys/crypto/fips_enabled")
+	if err != nil {
+		klog.Warningf("Failed to read /proc/sys/crypto/fips_enabled: %v; assuming FIPS is not enabled", err)
+		return result
+	}
+	if len(data) == 0 {
+		klog.Warningf("Got empty /proc/sys/crypto/fips_enabled; assuming FIPS is not enabled")
+		return result
+	}
+	result = strings.TrimSpace(string(data)) == "1"
+	klog.Infof("Read /proc/sys/crypto/fips_enabled: data=%s, result=%v", string(data), result)
+	return result
+}
+
 func startServiceCAController(ctx context.Context, cfg *config.Config, kubeconfigPath string) error {
 	var (
 		//TODO: fix the rolebinding and sa
@@ -230,7 +266,7 @@ func startIngressController(ctx context.Context, cfg *config.Config, kubeconfigP
 		return err
 	}
 
-	extraParams, err := generateIngressParams(cfg)
+	extraParams, err := generateIngressParams(cfg, isFIPSEnabled)
 	if err != nil {
 		return err
 	}
@@ -431,7 +467,7 @@ func validateClientTLS(patterns []string) error {
 	return nil
 }
 
-func generateIngressParams(cfg *config.Config) (assets.RenderParams, error) {
+func generateIngressParams(cfg *config.Config, fipsEnabled bool) (assets.RenderParams, error) {
 	routerMode := "v4"
 	if cfg.IsIPv6() {
 		routerMode = "v4v6"
@@ -472,12 +508,34 @@ func generateIngressParams(cfg *config.Config) (assets.RenderParams, error) {
 		}
 	}
 
+	// On FIPS-enabled clusters, remove non-FIPS-compliant TLS 1.3 cipher
+	// suites (e.g. TLS_CHACHA20_POLY1305_SHA256). HAProxy would fail TLS
+	// handshakes when a client offers a non-FIPS cipher first if that cipher
+	// is listed in ssl-default-bind-ciphersuites but excluded by the OS FIPS policy.
+	if fipsEnabled {
+		fipsCiphers := tls13Ciphers[:0]
+		for _, c := range tls13Ciphers {
+			if fipsApprovedTLS13Ciphers.Has(c) {
+				fipsCiphers = append(fipsCiphers, c)
+			}
+		}
+		tls13Ciphers = fipsCiphers
+	}
+
 	RouterCiphers := strings.Join(otherCiphers, ":")
 	RouterCiphersSuites := ""
 	if len(tls13Ciphers) != 0 {
 		RouterCiphersSuites = strings.Join(tls13Ciphers, ":")
 	}
 
+	// Default TLS supportedGroups (curves) include X25519MLKEM768 for
+	// post-quantum readiness. In FIPS mode, ML-KEM and X25519 are not
+	// supported by OpenSSL FIPS 140-3.
+	tlsCurves := "X25519MLKEM768:X25519:P-256:P-384:P-521"
+	if fipsEnabled {
+		tlsCurves = "P-256:P-384:P-521"
+	}
+
 	var RouterSSLMinVersion string
 	switch tlsProfileSpec.MinTLSVersion {
 	// TLS 1.0 is not supported, convert to TLS 1.1.
@@ -569,6 +627,7 @@ func generateIngressParams(cfg *config.Config) (assets.RenderParams, error) {
 		"RouterCiphers":               RouterCiphers,
 		"RouterCiphersSuites":         RouterCiphersSuites,
 		"RouterSSLMinVersion":         RouterSSLMinVersion,
+		"RouterTLSCurves":             tlsCurves,
 		"RouterAllowWildcardRoutes":   RouterAllowWildcardRoutes,
 		"ClientCAMapName":             clientCAMapName,
 		"ClientAuthPolicy":            clientAuthPolicy,
diff --git a/pkg/components/controllers_test.go b/pkg/components/controllers_test.go
new file mode 100644
index 0000000000..5e0e700c78
--- /dev/null
+++ b/pkg/components/controllers_test.go
@@ -0,0 +1,139 @@
+package components
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	configv1 "github.com/openshift/api/config/v1"
+	"github.com/openshift/microshift/pkg/assets"
+	"github.com/openshift/microshift/pkg/config"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/utils/ptr"
+)
+
+func newTestConfig() *config.Config {
+	return &config.Config{
+		DNS: config.DNS{BaseDomain: "example.com"},
+		Network: config.Network{
+			ClusterNetwork: []string{"10.42.0.0/16"},
+			ServiceNetwork: []string{"10.43.0.0/16"},
+		},
+		Ingress: config.IngressConfig{
+			Ports: config.IngressPortsConfig{
+				Http:  ptr.To(80),
+				Https: ptr.To(443),
+			},
+			TuningOptions: config.IngressControllerTuningOptions{
+				HeaderBufferBytes:           32768,
+				HeaderBufferMaxRewriteBytes: 8192,
+				HealthCheckInterval:         &metav1.Duration{Duration: 5 * time.Second},
+				ClientTimeout:               &metav1.Duration{Duration: 30 * time.Second},
+				ClientFinTimeout:            &metav1.Duration{Duration: 1 * time.Second},
+				ServerTimeout:               &metav1.Duration{Duration: 30 * time.Second},
+				ServerFinTimeout:            &metav1.Duration{Duration: 1 * time.Second},
+				TunnelTimeout:               &metav1.Duration{Duration: 1 * time.Hour},
+				TLSInspectDelay:             &metav1.Duration{Duration: 5 * time.Second},
+				ThreadCount:                 4,
+				MaxConnections:              50000,
+			},
+			ForwardedHeaderPolicy: "Append",
+			TLSSecurityProfile: &configv1.TLSSecurityProfile{
+				Type: configv1.TLSProfileIntermediateType,
+			},
+			ServingCertificateSecret: "router-certs-default",
+			DefaultHttpVersionPolicy: 1,
+			LogEmptyRequests:         "Log",
+			HTTPEmptyRequestsPolicy:  "Respond",
+			AccessLogging: config.AccessLogging{
+				Status: config.AccessLoggingDisabled,
+			},
+		},
+	}
+}
+
+func requireStringParam(t *testing.T, params assets.RenderParams, key string) string {
+	t.Helper()
+	v, ok := params[key]
+	if !ok {
+		t.Fatalf("missing param %q", key)
+	}
+	s, ok := v.(string)
+	if !ok {
+		t.Fatalf("param %q has type %T, want string", key, v)
+	}
+	return s
+}
+
+func TestGenerateIngressParamsFIPSCiphers(t *testing.T) {
+	t.Run("FIPS enabled filters non-FIPS TLS 1.3 ciphers", func(t *testing.T) {
+		cfg := newTestConfig()
+		params, err := generateIngressParams(cfg, true)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		cipherSuites := requireStringParam(t, params, "RouterCiphersSuites")
+		if strings.Contains(cipherSuites, "TLS_CHACHA20_POLY1305_SHA256") {
+			t.Errorf("FIPS mode should filter out TLS_CHACHA20_POLY1305_SHA256, got: %s", cipherSuites)
+		}
+		if !strings.Contains(cipherSuites, "TLS_AES_128_GCM_SHA256") {
+			t.Errorf("FIPS mode should keep TLS_AES_128_GCM_SHA256, got: %s", cipherSuites)
+		}
+		if !strings.Contains(cipherSuites, "TLS_AES_256_GCM_SHA384") {
+			t.Errorf("FIPS mode should keep TLS_AES_256_GCM_SHA384, got: %s", cipherSuites)
+		}
+	})
+
+	t.Run("non-FIPS keeps all TLS 1.3 ciphers", func(t *testing.T) {
+		cfg := newTestConfig()
+		params, err := generateIngressParams(cfg, false)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		cipherSuites := requireStringParam(t, params, "RouterCiphersSuites")
+		if !strings.Contains(cipherSuites, "TLS_CHACHA20_POLY1305_SHA256") {
+			t.Errorf("non-FIPS mode should keep TLS_CHACHA20_POLY1305_SHA256, got: %s", cipherSuites)
+		}
+	})
+}
+
+func TestGenerateIngressParamsFIPSCurves(t *testing.T) {
+	t.Run("FIPS enabled uses only NIST curves", func(t *testing.T) {
+		cfg := newTestConfig()
+		params, err := generateIngressParams(cfg, true)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		curves := requireStringParam(t, params, "RouterTLSCurves")
+		if strings.Contains(curves, "X25519MLKEM768") {
+			t.Errorf("FIPS mode should exclude X25519MLKEM768, got: %s", curves)
+		}
+		for _, c := range strings.Split(curves, ":") {
+			if c == "X25519" {
+				t.Errorf("FIPS mode should exclude X25519, got: %s", curves)
+			}
+		}
+		if curves != "P-256:P-384:P-521" {
+			t.Errorf("FIPS mode curves should be P-256:P-384:P-521, got: %s", curves)
+		}
+	})
+
+	t.Run("non-FIPS includes PQC hybrid curve", func(t *testing.T) {
+		cfg := newTestConfig()
+		params, err := generateIngressParams(cfg, false)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		curves := requireStringParam(t, params, "RouterTLSCurves")
+		if !strings.Contains(curves, "X25519MLKEM768") {
+			t.Errorf("non-FIPS mode should include X25519MLKEM768, got: %s", curves)
+		}
+		if curves != "X25519MLKEM768:X25519:P-256:P-384:P-521" {
+			t.Errorf("non-FIPS mode curves should be X25519MLKEM768:X25519:P-256:P-384:P-521, got: %s", curves)
+		}
+	})
+}
diff --git a/test/suites/optional/tls-scanner.robot b/test/suites/optional/tls-scanner.robot
index 1a26973871..367ca307c8 100644
--- a/test/suites/optional/tls-scanner.robot
+++ b/test/suites/optional/tls-scanner.robot
@@ -49,6 +49,10 @@ TLS Scanner Host Scan Completes And Produces Artifacts
     ...    Cleanup TLS Scanner Job
     ...    Ensure Cluster Reader Role Deleted
 
+Ingress Router TLS Curves supports ML-KEM Post Quantum Curves
+    [Documentation]    Verify TLS curve negotiation with openssl from inside the router pod.
+    Verify ML-KEM Post Quantum Curve Negotiation
+
 
 *** Keywords ***
 Check Required Scanner Variables
@@ -123,3 +127,23 @@ Cleanup TLS Scanner Job
     IF    '${TLS_SCANNER_DIR}' != ''
         Run Keyword And Ignore Error    Remove Directory    ${TLS_SCANNER_DIR}    recursive=True
     END
+
+Verify ML-KEM Post Quantum Curve Negotiation
+    [Documentation]    Verify X25519MLKEM768 post-quantum hybrid key exchange
+    ...    negotiates successfully via oc exec into the router pod, which
+    ...    has OpenSSL 3.5+ (the host OpenSSL may be too old for ML-KEM).
+    ...    Skipped on FIPS clusters where ML-KEM is not configured.
+    ${curves}=    Oc Get JsonPath    deployment    openshift-ingress    router-default
+    ...    .spec.template.spec.containers[0].env[?(@.name=="ROUTER_CURVES")].value
+    Skip If    "X25519MLKEM768" not in """${curves}"""
+    ...    ROUTER_CURVES does not include X25519MLKEM768 (FIPS mode); skipping ML-KEM test
+    ${router_ip}=    Oc Get JsonPath    svc    openshift-ingress    router-default
+    ...    .spec.clusterIP
+    ${pod_name}=    Oc Get JsonPath    pod    openshift-ingress    ${EMPTY}
+    ...    .items[0].metadata.name
+    ${output}=    Oc Exec    ${pod_name}
+    ...    echo Q | openssl s_client -connect ${router_ip}:443 -groups X25519MLKEM768 2>&1 || true
+    ...    ns=openshift-ingress
+    Should Contain    ${output}    Negotiated TLS1.3 group: X25519MLKEM768
+    ...    msg=ML-KEM post-quantum curve X25519MLKEM768 negotiation failed
+    Log    Post-quantum ML-KEM negotiation verified: OK