diff --git a/src/Build/Instance/ProjectInstance.cs b/src/Build/Instance/ProjectInstance.cs
index 092addf25e3..fe0cdee00e6 100644
--- a/src/Build/Instance/ProjectInstance.cs
+++ b/src/Build/Instance/ProjectInstance.cs
@@ -845,7 +845,7 @@ private ProjectInstance(ProjectInstance that, bool isImmutable, RequestedProject
                             _globalProperties.Set(globalProperty.DeepClone(isImmutable: true));
                         }
 
-                        var environmentProperty = that._environmentVariableProperties.GetProperty(desiredProperty);
+                        var environmentProperty = that._environmentVariableProperties?.GetProperty(desiredProperty);
                         if (environmentProperty != null)
                         {
                             _environmentVariableProperties.Set(environmentProperty.DeepClone(isImmutable: true));