diff --git a/NHibernate.Property.Expression/NHibernate.Property.Expression.csproj b/NHibernate.Property.Expression/NHibernate.Property.Expression.csproj
index 9c5361d..bed42cc 100644
--- a/NHibernate.Property.Expression/NHibernate.Property.Expression.csproj
+++ b/NHibernate.Property.Expression/NHibernate.Property.Expression.csproj
@@ -28,7 +28,7 @@
   </PropertyGroup>
   
   <ItemGroup>
-    <PackageReference Include="NHibernate" Version="5.1.0" />
+    <PackageReference Include="NHibernate" Version="5.5.1" />
     
     <!-- SourceLink , see https://github.com/ctaggart/SourceLink -->
     <PackageReference Include="SourceLink.Copy.PdbFiles" Version="2.8.3" PrivateAssets="All" />
diff --git a/NHibernate.Property.Expressions.Tests/NHibernate.Property.Expressions.Tests.csproj b/NHibernate.Property.Expressions.Tests/NHibernate.Property.Expressions.Tests.csproj
index 5894159..4bb0787 100644
--- a/NHibernate.Property.Expressions.Tests/NHibernate.Property.Expressions.Tests.csproj
+++ b/NHibernate.Property.Expressions.Tests/NHibernate.Property.Expressions.Tests.csproj
@@ -14,7 +14,7 @@
     <PackageReference Include="MSTest.TestAdapter" Version="3.4.0" />
     <PackageReference Include="MSTest.TestFramework" Version="3.4.0" />
     <PackageReference Include="FluentAssertions" Version="6.12.0" />
-    <PackageReference Include="NHibernate" Version="5.1.0" />
+    <PackageReference Include="NHibernate" Version="5.5.1" />
     <PackageReference Include="NUnit" Version="3.14.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
     <PackageReference Include="System.Data.SQLite.Core" Version="1.0.118" />