diff --git a/TestSuite/foreach8.pas b/TestSuite/foreach8.pas
new file mode 100644
index 000000000..7bfbd8031
--- /dev/null
+++ b/TestSuite/foreach8.pas
@@ -0,0 +1,14 @@
+type
+  t1 = class(List<integer>) end;
+  
+begin
+  var l := new t1;
+  l.Add(1);
+  l.Add(2);
+  var i := 1;
+  foreach var x in l do
+  begin
+    assert(i = x);
+    Inc(i);
+  end;
+end.
\ No newline at end of file
diff --git a/TreeConverter/TreeConversion/syntax_tree_visitor.cs b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
index 6cc9c9e8a..c8c015c0a 100644
--- a/TreeConverter/TreeConversion/syntax_tree_visitor.cs
+++ b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
@@ -17921,7 +17921,11 @@ namespace PascalABCCompiler.TreeConverter
             // Попытка реализовать IEnumerable<T> натыкается на необходимость определять GetEnumerator, возвращающий IEnumerator и IEnumerator<T>
             {
                 if (tn == null || tn is null_type_node || tn.ImplementingInterfaces == null)
+                {
+                    if (tn != null && tn.base_type != null)
+                        return FindIEnumerableElementType(tn.base_type, ref elem_type, out sys_coll_ienum);
                     return false;
+                }
 
                 if (tn.element_type != null && tn.type_special_kind != SemanticTree.type_special_kind.typed_file) // еще может быть множество set of T - 22.02.16 SSM
                 {
@@ -17968,6 +17972,8 @@ namespace PascalABCCompiler.TreeConverter
                     }
                 }
             }
+            if (tn != null && tn.base_type != null)
+                return FindIEnumerableElementType(tn.base_type, ref elem_type, out sys_coll_ienum);
             return false;
         }