diff --git a/src/tests/GC/API/GC/TotalMemory.csproj b/src/tests/GC/API/GC/TotalMemory.csproj
index c98e67f9b1dcb7..27048c1d81d027 100644
--- a/src/tests/GC/API/GC/TotalMemory.csproj
+++ b/src/tests/GC/API/GC/TotalMemory.csproj
@@ -3,6 +3,10 @@
     <OutputType>Exe</OutputType>
     <CLRTestExecutionArguments />
     <CLRTestPriority>1</CLRTestPriority>
+    <!-- This test is failing under GCStress variations, so disabling it under GCStress till the issue is investigated:
+         Issue: https://github.com/dotnet/runtime/issues/63860
+    -->
+    <GCStressIncompatible>true</GCStressIncompatible>
   </PropertyGroup>
   <PropertyGroup>
     <!-- Set to 'Full' if the Debug? column is marked in the spreadsheet. Leave blank otherwise. -->
diff --git a/src/tests/GC/API/GC/TotalMemory2.csproj b/src/tests/GC/API/GC/TotalMemory2.csproj
index 05fccbfd27106a..eccd9b6b24523f 100644
--- a/src/tests/GC/API/GC/TotalMemory2.csproj
+++ b/src/tests/GC/API/GC/TotalMemory2.csproj
@@ -2,6 +2,10 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <CLRTestPriority>1</CLRTestPriority>
+    <!-- This test is failing under GCStress variations, so disabling it under GCStress till the issue is investigated:
+         Issue: https://github.com/dotnet/runtime/issues/63860
+    -->
+    <GCStressIncompatible>true</GCStressIncompatible>
   </PropertyGroup>
   <PropertyGroup>
     <!-- Set to 'Full' if the Debug? column is marked in the spreadsheet. Leave blank otherwise. -->