diff --git a/packages/fcl-json/src/jsonconf.pp b/packages/fcl-json/src/jsonconf.pp
index ce92b959e4..6da2bb9ea0 100644
--- a/packages/fcl-json/src/jsonconf.pp
+++ b/packages/fcl-json/src/jsonconf.pp
@@ -637,6 +637,7 @@ begin
         Node.Delete(L);
       end;
     end;
+  FModified:=True;  
 end;
 
 procedure TJSONConfig.DeleteValue(const APath: UnicodeString);
diff --git a/packages/fcl-json/tests/jsonconftest.pp b/packages/fcl-json/tests/jsonconftest.pp
index 3abc42727d..c93dc7d94b 100644
--- a/packages/fcl-json/tests/jsonconftest.pp
+++ b/packages/fcl-json/tests/jsonconftest.pp
@@ -179,7 +179,9 @@ begin
   C:=CreateConf('test.json');
   try
     C.SetValue('a',1);
+    C.Flush;
     C.DeleteValue('a');
+    AssertEquals('Modified set',True,C.Modified);
     AssertEquals('Delete value',0,C.GetValue('a',0));
     C.SetValue('b/a',1);
     C.SetValue('b/c',2);
@@ -187,7 +189,9 @@ begin
     AssertEquals('Delete value in subkey',0,C.GetValue('a',0));
     AssertEquals('Delete value only clears deleted value',2,C.GetValue('b/c',0));
     C.SetValue('b/a',1);
+    C.Flush;
     C.DeletePath('b');
+    AssertEquals('Modified set',True,C.Modified);
     AssertEquals('Delete path',0,C.GetValue('b/a',0));
     AssertEquals('Delete path deletes all values',0,C.GetValue('b/c',0));
     C.Clear;