diff --git a/cli/azd/pkg/azure/arm_template.go b/cli/azd/pkg/azure/arm_template.go
index 006fcde4848..8890fe73b0f 100644
--- a/cli/azd/pkg/azure/arm_template.go
+++ b/cli/azd/pkg/azure/arm_template.go
@@ -57,7 +57,7 @@ type ArmTemplateParameterDefinitions map[string]ArmTemplateParameterDefinition
 
 type ArmTemplateOutputs map[string]ArmTemplateOutput
 
-type ArmTemplateParameterAdditionalProperties struct {
+type ArmTemplateParameterAdditionalPropertiesProperties struct {
 	Type      string                     `json:"type"`
 	MinValue  *int                       `json:"minValue,omitempty"`
 	MaxValue  *int                       `json:"maxValue,omitempty"`
@@ -66,18 +66,52 @@ type ArmTemplateParameterAdditionalProperties struct {
 	Metadata  map[string]json.RawMessage `json:"metadata"`
 }
 
+type ArmTemplateParameterAdditionalPropertiesValue struct {
+	props *ArmTemplateParameterAdditionalPropertiesProperties
+}
+
+func (v ArmTemplateParameterAdditionalPropertiesValue) HasAdditionalProperties() bool {
+	return v.props != nil
+}
+
+func (v ArmTemplateParameterAdditionalPropertiesValue) Properties() ArmTemplateParameterAdditionalPropertiesProperties {
+	return *v.props
+}
+
+func (v *ArmTemplateParameterAdditionalPropertiesValue) UnmarshalJSON(data []byte) error {
+	if string(data) == "false" {
+		return nil
+	}
+
+	var props ArmTemplateParameterAdditionalPropertiesProperties
+	if err := json.Unmarshal(data, &props); err != nil {
+		return err
+	}
+
+	v.props = &props
+	return nil
+}
+
+func (v *ArmTemplateParameterAdditionalPropertiesValue) MarshalJSON() ([]byte, error) {
+	if v.props == nil {
+		return []byte("false"), nil
+	}
+
+	return json.Marshal(v.props)
+}
+
 type ArmTemplateParameterDefinition struct {
-	Type                 string                                   `json:"type"`
-	DefaultValue         any                                      `json:"defaultValue"`
-	AllowedValues        *[]any                                   `json:"allowedValues,omitempty"`
-	MinValue             *int                                     `json:"minValue,omitempty"`
-	MaxValue             *int                                     `json:"maxValue,omitempty"`
-	MinLength            *int                                     `json:"minLength,omitempty"`
-	MaxLength            *int                                     `json:"maxLength,omitempty"`
-	Metadata             map[string]json.RawMessage               `json:"metadata"`
-	Ref                  string                                   `json:"$ref"`
-	Properties           ArmTemplateParameterDefinitions          `json:"properties,omitempty"`
-	AdditionalProperties ArmTemplateParameterAdditionalProperties `json:"additionalProperties,omitempty"`
+	Type                 string                                         `json:"type"`
+	DefaultValue         any                                            `json:"defaultValue"`
+	AllowedValues        *[]any                                         `json:"allowedValues,omitempty"`
+	MinValue             *int                                           `json:"minValue,omitempty"`
+	MaxValue             *int                                           `json:"maxValue,omitempty"`
+	MinLength            *int                                           `json:"minLength,omitempty"`
+	MaxLength            *int                                           `json:"maxLength,omitempty"`
+	Metadata             map[string]json.RawMessage                     `json:"metadata"`
+	Ref                  string                                         `json:"$ref"`
+	Properties           ArmTemplateParameterDefinitions                `json:"properties,omitempty"`
+	AdditionalProperties *ArmTemplateParameterAdditionalPropertiesValue `json:"additionalProperties,omitempty"`
 }
 
 func (d *ArmTemplateParameterDefinition) Secure() bool {
diff --git a/cli/azd/pkg/infra/provisioning/bicep/bicep_provider_test.go b/cli/azd/pkg/infra/provisioning/bicep/bicep_provider_test.go
index 0c0d4cff1f6..08928cf3fdb 100644
--- a/cli/azd/pkg/infra/provisioning/bicep/bicep_provider_test.go
+++ b/cli/azd/pkg/infra/provisioning/bicep/bicep_provider_test.go
@@ -1032,9 +1032,10 @@ func TestUserDefinedTypes(t *testing.T) {
 		},
 		objectParam.Properties)
 	require.NotNil(t, objectParam.AdditionalProperties)
+	require.True(t, objectParam.AdditionalProperties.HasAdditionalProperties())
 	require.Equal(
 		t,
-		azure.ArmTemplateParameterAdditionalProperties{
+		azure.ArmTemplateParameterAdditionalPropertiesProperties{
 			Type:      "string",
 			MinLength: to.Ptr(10),
 			Metadata: map[string]json.RawMessage{
@@ -1042,7 +1043,7 @@ func TestUserDefinedTypes(t *testing.T) {
 				"fromDefinitionBar": []byte(`"bar"`),
 			},
 		},
-		objectParam.AdditionalProperties)
+		objectParam.AdditionalProperties.Properties())
 	require.NotNil(t, objectParam.Metadata)
 	require.Equal(
 		t,
@@ -1056,6 +1057,21 @@ func TestUserDefinedTypes(t *testing.T) {
 		},
 		objectParam.Metadata)
 
+	sealedObjectParam, exists := template.Parameters["sealedObjectParam"]
+	require.True(t, exists)
+	require.Equal(t, "object", sealedObjectParam.Type)
+	require.Nil(t, sealedObjectParam.AllowedValues)
+	require.NotNil(t, sealedObjectParam.Properties)
+	require.Equal(
+		t,
+		azure.ArmTemplateParameterDefinitions{
+			"name": {Type: "string"},
+			"sku":  {Type: "string"},
+		},
+		sealedObjectParam.Properties)
+	require.NotNil(t, sealedObjectParam.AdditionalProperties)
+	require.False(t, sealedObjectParam.AdditionalProperties.HasAdditionalProperties())
+
 	// output resolves just the type. Value and Metadata should persist
 	customOutput, exists := template.Outputs["customOutput"]
 	require.True(t, exists)
@@ -1211,6 +1227,18 @@ const userDefinedParamsSample = `{
 			"fromDefinitionFoo": "foo",
 			"fromDefinitionBar": "bar"
 		}
+	  },
+	  "sealedObjectType": {
+		"type": "object",
+		"properties": {
+		  "name": {
+			"type": "string"
+		  },
+		  "sku": {
+			"type": "string"
+		  }
+		},
+		"additionalProperties": false
 	  }
 	},
 	"parameters": {
@@ -1242,6 +1270,9 @@ const userDefinedParamsSample = `{
 			"fromDefinitionBar": "override",
 			"fromParameter": "parameter"
 		  }
+	  },
+	  "sealedObjectParam": {
+		"$ref": "#/definitions/sealedObjectType"
 	  }
 	},
 	"resources": {},