diff --git a/IPython/core/magics/execution.py b/IPython/core/magics/execution.py
index 769a062..ef9ae1b 100644
--- a/IPython/core/magics/execution.py
+++ b/IPython/core/magics/execution.py
@@ -940,7 +940,8 @@ python-profiler package from non-free.""")
 
     @skip_doctest
     @line_cell_magic
-    def timeit(self, line='', cell=None):
+    @needs_local_scope
+    def timeit(self, line='', cell=None, local_ns=None):
         """Time execution of a Python statement or expression
 
         Usage, in line mode:
@@ -1074,7 +1075,16 @@ python-profiler package from non-free.""")
         tc = clock()-t0
 
         ns = {}
-        exec(code, self.shell.user_ns, ns)
+        glob = self.shell.user_ns
+        # handles global vars with same name as local vars. We store them in conflict_globs.
+        if local_ns is not None:
+            conflict_globs = {}
+            for var_name, var_val in glob.items():
+                if var_name in local_ns:
+                    conflict_globs[var_name] = var_val
+            glob.update(local_ns)
+            
+        exec(code, glob, ns)
         timer.inner = ns["inner"]
 
         # This is used to check if there is a huge difference between the
@@ -1093,6 +1103,11 @@ python-profiler package from non-free.""")
         worst = max(all_runs) / number
         timeit_result = TimeitResult(number, repeat, best, worst, all_runs, tc, precision)
 
+        # Restore global vars from conflict_globs
+        if local_ns is not None:
+            if len(conflict_globs) > 0:
+                glob.update(conflict_globs)
+                
         if not quiet :
             # Check best timing is greater than zero to avoid a
             # ZeroDivisionError.