diff --git a/llvm/tools/opt-viewer/opt-viewer.py b/llvm/tools/opt-viewer/opt-viewer.py
--- a/llvm/tools/opt-viewer/opt-viewer.py
+++ b/llvm/tools/opt-viewer/opt-viewer.py
@@ -3,9 +3,9 @@
 from __future__ import print_function
 
 import argparse
-import cgi
 import errno
 import functools
+import html
 import io
 from multiprocessing import cpu_count
 import os.path
@@ -197,7 +197,7 @@
         self.max_hottest_remarks_on_index = max_hottest_remarks_on_index
 
     def render_entry(self, r, odd):
-        escaped_name = cgi.escape(r.DemangledFunctionName)
+        escaped_name = html.escape(r.DemangledFunctionName)
         print(u'''
 <tr>
 <td class=\"column-entry-{odd}\"><a href={r.Link}>{r.DebugLocString}</a></td>
diff --git a/llvm/tools/opt-viewer/optrecord.py b/llvm/tools/opt-viewer/optrecord.py
--- a/llvm/tools/opt-viewer/optrecord.py
+++ b/llvm/tools/opt-viewer/optrecord.py
@@ -11,7 +11,7 @@
     print("For faster parsing, you may want to install libYAML for PyYAML")
     from yaml import Loader
 
-import cgi
+import html
 from collections import defaultdict
 import fnmatch
 import functools
@@ -159,7 +159,7 @@
         (key, value) = list(mapping.items())[0]
 
         if key == 'Caller' or key == 'Callee' or key == 'DirectCallee':
-            value = cgi.escape(self.demangle(value))
+            value = html.escape(self.demangle(value))
 
         if dl and key != 'Caller':
             dl_dict = dict(list(dl))