diff --git a/Lib/cgitb.py b/Lib/cgitb.py
--- a/Lib/cgitb.py
+++ b/Lib/cgitb.py
@@ -125,9 +125,19 @@
         args, varargs, varkw, locals = inspect.getargvalues(frame)
         call = ''
         if func != '?':
-            call = 'in ' + strong(func) + \
+            try:
+                call = 'in ' + strong(func) + \
                 inspect.formatargvalues(args, varargs, varkw, locals,
                     formatvalue=lambda value: '=' + pydoc.html.repr(value))
+            except Exception as e:
+                import traceback
+                print '-'*80
+                print repr(e)
+                traceback.print_exc()
+                print 'args', args
+                print 'varargs', varargs
+                print '-'*80
+                return ''
 
         highlight = {}
         def reader(lnum=[lnum]):
diff --git a/Lib/inspect.py b/Lib/inspect.py
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -867,6 +867,14 @@
         specs.append(formatvarkw(varkw))
     return '(' + string.join(specs, ', ') + ')'
 
+# a placeholder with <deleted> as repr (using a string would have '<deleted>'
+# with quotes).  This is used in formatargvalues
+class _Deleted(object):
+    def __repr__(self):
+        return '<deleted>'
+_deleted = _Deleted()
+del _Deleted
+
 def formatargvalues(args, varargs, varkw, locals,
                     formatarg=str,
                     formatvarargs=lambda name: '*' + name,
@@ -881,7 +889,7 @@
     argument is an optional function to format the sequence of arguments."""
     def convert(name, locals=locals,
                 formatarg=formatarg, formatvalue=formatvalue):
-        return formatarg(name) + formatvalue(locals[name])
+        return formatarg(name) + formatvalue(locals.get(name, _deleted))
     specs = []
     for i in range(len(args)):
         specs.append(strseq(args[i], convert, join))
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -193,6 +193,14 @@
         self.assertEqual(inspect.formatargvalues(args, varargs, varkw, locals),
              '(a=7, b=8, c=9, d=3, (e=4, (f=5,)), *g=(), **h={})')
 
+    def test_formatargvalues_deleted_args(self):
+        def fun(a, b, x, y):
+            del b, y
+            return inspect.currentframe()
+        args = inspect.getargvalues(fun(2, 4, 8, 16))
+        self.assertEqual(inspect.formatargvalues(*args),
+                         '(a=2, b=<deleted>, x=8, y=<deleted>)')
+
 class GetSourceBase(unittest.TestCase):
     # Subclasses must override.
     fodderFile = None