diff --git a/src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs b/src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs
index a1648c1da6d8b2..7e352915ac39e3 100644
--- a/src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs
+++ b/src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs
@@ -43,6 +43,7 @@ public static partial class PlatformDetection
         public static bool IsNotCoreClrInterpreter => !IsCoreClrInterpreter;
         public static bool IsFreeBSD => RuntimeInformation.IsOSPlatform(OSPlatform.Create("FREEBSD"));
         public static bool IsNetBSD => RuntimeInformation.IsOSPlatform(OSPlatform.Create("NETBSD"));
+        public static bool IsOpenBSD => RuntimeInformation.IsOSPlatform(OSPlatform.Create("OPENBSD"));
         public static bool IsAndroid => RuntimeInformation.IsOSPlatform(OSPlatform.Create("ANDROID"));
         public static bool IsNotAndroid => !IsAndroid;
         public static bool IsAndroidX86 => IsAndroid && IsX86Process;
@@ -64,7 +65,7 @@ public static partial class PlatformDetection
         public static bool IsAppleMobile => IsMacCatalyst || IsiOS || IstvOS;
         public static bool IsNotAppleMobile => !IsAppleMobile;
         public static bool IsNotNetFramework => !IsNetFramework;
-        public static bool IsBsdLike => IsApplePlatform || IsFreeBSD || IsNetBSD;
+        public static bool IsBsdLike => IsApplePlatform || IsFreeBSD || IsNetBSD || IsOpenBSD;
 
         public static bool IsArmProcess => RuntimeInformation.ProcessArchitecture == Architecture.Arm;
         public static bool IsNotArmProcess => !IsArmProcess;
diff --git a/src/libraries/System.IO.FileSystem.Watcher/src/System.IO.FileSystem.Watcher.csproj b/src/libraries/System.IO.FileSystem.Watcher/src/System.IO.FileSystem.Watcher.csproj
index c8fd0e835ddbbe..71b0bcd53fd14f 100644
--- a/src/libraries/System.IO.FileSystem.Watcher/src/System.IO.FileSystem.Watcher.csproj
+++ b/src/libraries/System.IO.FileSystem.Watcher/src/System.IO.FileSystem.Watcher.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-linux;$(NetCoreAppCurrent)-osx;$(NetCoreAppCurrent)-maccatalyst;$(NetCoreAppCurrent)-freebsd;$(NetCoreAppCurrent)</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-linux;$(NetCoreAppCurrent)-osx;$(NetCoreAppCurrent)-maccatalyst;$(NetCoreAppCurrent)-freebsd;$(NetCoreAppCurrent)-openbsd;$(NetCoreAppCurrent)</TargetFrameworks>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
   </PropertyGroup>
@@ -77,7 +77,7 @@
              Link="Common\Interop\Unix\Interop.PathConf.cs" />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'linux' or '$(TargetPlatformIdentifier)' == 'freebsd'">
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'linux' or '$(TargetPlatformIdentifier)' == 'freebsd' or '$(TargetPlatformIdentifier)' == 'openbsd'">
     <Compile Include="System\IO\FileSystemWatcher.Linux.cs" />
     <Compile Include="$(CommonPath)Interop\Linux\System.Native\Interop.INotify.cs"
              Link="Common\Interop\Linux\Interop.inotify.cs" />
diff --git a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.Directory.Move.cs b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.Directory.Move.cs
index 7c3d9415d1b8b3..466a9e97ad5bb1 100644
--- a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.Directory.Move.cs
+++ b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.Directory.Move.cs
@@ -53,7 +53,7 @@ public void Directory_Move_Multiple_From_Watched_To_Unwatched(int filesCount)
         }
 
         [Theory]
-        [SkipOnPlatform(TestPlatforms.FreeBSD, "Not supported on FreeBSD.")]
+        [SkipOnPlatform(TestPlatforms.FreeBSD | TestPlatforms.OpenBSD, "Not supported on FreeBSD and OpenBSD.")]
         [InlineData(1)]
         [InlineData(2)]
         [InlineData(3)]
diff --git a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.File.Move.cs b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.File.Move.cs
index 7c7bbfc5529e29..848d95d0741a56 100644
--- a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.File.Move.cs
+++ b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.File.Move.cs
@@ -58,6 +58,7 @@ public void File_Move_Multiple_From_Watched_To_Unwatched(int filesCount)
         }
 
         [Theory]
+        [SkipOnPlatform(TestPlatforms.OpenBSD, "libinotify on OpenBSD does not preserve event ordering.")]
         [InlineData(1)]
         [InlineData(2)]
         [InlineData(3)]
diff --git a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.cs b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.cs
index cde4fff57c5966..2e92932211a032 100644
--- a/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.cs
+++ b/src/libraries/System.IO.FileSystem.Watcher/tests/FileSystemWatcher.cs
@@ -171,6 +171,7 @@ public void BeginInit_PausesEnableRaisingEvents()
         [Theory]
         [InlineData(true)]
         [InlineData(false)]
+        [SkipOnPlatform(TestPlatforms.OpenBSD, "libinotify on OpenBSD can lose the Created event for a file that is created and immediately deleted on a freshly-started watch.")]
         public void EndInit_ResumesPausedEnableRaisingEvents(bool setBeforeBeginInit)
         {
             FileSystemWatcherTest.Execute(() =>
diff --git a/src/libraries/System.IO.FileSystem.Watcher/tests/System.IO.FileSystem.Watcher.Tests.csproj b/src/libraries/System.IO.FileSystem.Watcher/tests/System.IO.FileSystem.Watcher.Tests.csproj
index 1e43fca4491b34..e69c3da9b186d8 100644
--- a/src/libraries/System.IO.FileSystem.Watcher/tests/System.IO.FileSystem.Watcher.Tests.csproj
+++ b/src/libraries/System.IO.FileSystem.Watcher/tests/System.IO.FileSystem.Watcher.Tests.csproj
@@ -2,7 +2,7 @@
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-linux;$(NetCoreAppCurrent)-osx;$(NetCoreAppCurrent)-maccatalyst;$(NetCoreAppCurrent)-freebsd</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-linux;$(NetCoreAppCurrent)-osx;$(NetCoreAppCurrent)-maccatalyst;$(NetCoreAppCurrent)-freebsd;$(NetCoreAppCurrent)-openbsd</TargetFrameworks>
     <IgnoreForCI Condition="'$(TargetOS)' == 'browser' or '$(TargetOS)' == 'iossimulator' or '$(TargetOS)' == 'ios' or '$(TargetOS)' == 'tvossimulator' or '$(TargetOS)' == 'tvos'">true</IgnoreForCI>
   </PropertyGroup>
   <ItemGroup>
diff --git a/src/native/libs/System.Native/extra_libs.cmake b/src/native/libs/System.Native/extra_libs.cmake
index b9d18b61a429bc..29f32ce928e403 100644
--- a/src/native/libs/System.Native/extra_libs.cmake
+++ b/src/native/libs/System.Native/extra_libs.cmake
@@ -8,6 +8,8 @@ macro(append_extra_system_libs NativeLibsExtra)
         list(APPEND ${NativeLibsExtra} ${INOTIFY_LIBRARY})
     elseif (CLR_CMAKE_TARGET_OPENBSD)
         list(APPEND ${NativeLibsExtra} pthread)
+        find_library(INOTIFY_LIBRARY inotify HINTS ${CROSS_ROOTFS}/usr/local/lib/inotify)
+        list(APPEND ${NativeLibsExtra} ${INOTIFY_LIBRARY})
     elseif (CLR_CMAKE_TARGET_SUNOS)
         list(APPEND ${NativeLibsExtra} socket nsl)
     elseif (CLR_CMAKE_TARGET_HAIKU)
diff --git a/src/native/libs/configure.cmake b/src/native/libs/configure.cmake
index 4dcb1409f99233..03d10f36842c12 100644
--- a/src/native/libs/configure.cmake
+++ b/src/native/libs/configure.cmake
@@ -22,8 +22,8 @@ elseif (CLR_CMAKE_TARGET_FREEBSD)
     include_directories(SYSTEM ${CROSS_ROOTFS}/usr/local/include)
     set(CMAKE_REQUIRED_INCLUDES ${CROSS_ROOTFS}/usr/local/include)
 elseif (CLR_CMAKE_TARGET_OPENBSD)
-    include_directories(SYSTEM ${CROSS_ROOTFS}/usr/local/include ${CROSS_ROOTFS}/usr/local/heimdal/include)
-    set(CMAKE_REQUIRED_INCLUDES ${CROSS_ROOTFS}/usr/local/include ${CROSS_ROOTFS}/usr/local/heimdal/include)
+    include_directories(SYSTEM ${CROSS_ROOTFS}/usr/local/include ${CROSS_ROOTFS}/usr/local/heimdal/include ${CROSS_ROOTFS}/usr/local/include/inotify)
+    set(CMAKE_REQUIRED_INCLUDES ${CROSS_ROOTFS}/usr/local/include ${CROSS_ROOTFS}/usr/local/heimdal/include ${CROSS_ROOTFS}/usr/local/include/inotify)
 elseif (CLR_CMAKE_TARGET_SUNOS)
     # requires /opt/tools when building in Global Zone (GZ)
     include_directories(SYSTEM /opt/local/include /opt/tools/include)
@@ -1052,8 +1052,10 @@ endif()
 set (CMAKE_REQUIRED_LIBRARIES ${PREVIOUS_CMAKE_REQUIRED_LIBRARIES})
 
 set (PREVIOUS_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-if (HAVE_SYS_INOTIFY_H AND (CLR_CMAKE_TARGET_FREEBSD OR CLR_CMAKE_TARGET_OPENBSD))
+if (HAVE_SYS_INOTIFY_H AND CLR_CMAKE_TARGET_FREEBSD)
     set (CMAKE_REQUIRED_LIBRARIES "-linotify -L${CROSS_ROOTFS}/usr/local/lib")
+elseif (HAVE_SYS_INOTIFY_H AND CLR_CMAKE_TARGET_OPENBSD)
+    set (CMAKE_REQUIRED_LIBRARIES "-linotify -lpthread -L${CROSS_ROOTFS}/usr/local/lib/inotify")
 endif()
 
 check_symbol_exists(