diff --git a/src/abseil-cpp/gen_build_yaml.py b/src/abseil-cpp/gen_build_yaml.py
index 2f32a3e25c7..889c44b4ea9 100755
--- a/src/abseil-cpp/gen_build_yaml.py
+++ b/src/abseil-cpp/gen_build_yaml.py
@@ -20,7 +20,7 @@ import yaml
 BUILDS_YAML_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                 'preprocessed_builds.yaml')
 with open(BUILDS_YAML_PATH) as f:
-    builds = yaml.load(f)
+    builds = yaml.load(f, Loader=yaml.FullLoader)
 
 for build in builds:
     build['build'] = 'private'
diff --git a/test/cpp/naming/gen_build_yaml.py b/test/cpp/naming/gen_build_yaml.py
index 59d12be92a9..eb278572af2 100755
--- a/test/cpp/naming/gen_build_yaml.py
+++ b/test/cpp/naming/gen_build_yaml.py
@@ -65,7 +65,7 @@ def _resolver_test_cases(resolver_component_data):
 def main():
     resolver_component_data = ''
     with open('test/cpp/naming/resolver_test_record_groups.yaml') as f:
-        resolver_component_data = yaml.load(f)
+        resolver_component_data = yaml.load(f, Loader=yaml.FullLoader)
 
     json = {
         'resolver_tests_common_zone_name':
diff --git a/tools/buildgen/build_cleaner.py b/tools/buildgen/build_cleaner.py
index cda6f715123..b044cb7da9b 100755
--- a/tools/buildgen/build_cleaner.py
+++ b/tools/buildgen/build_cleaner.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -83,7 +83,7 @@ def cleaned_build_yaml_dict_as_string(indict):
 if __name__ == '__main__':
     for filename in sys.argv[1:]:
         with open(filename) as f:
-            js = yaml.load(f)
+            js = yaml.load(f, Loader=yaml.FullLoader)
         output = cleaned_build_yaml_dict_as_string(js)
         if TEST:
             with open(filename) as f:
diff --git a/tools/buildgen/generate_projects.sh b/tools/buildgen/generate_projects.sh
index 81c16153c71..9b5c0f50bb2 100755
--- a/tools/buildgen/generate_projects.sh
+++ b/tools/buildgen/generate_projects.sh
@@ -18,6 +18,9 @@ set -e
 
 export TEST=${TEST:-false}
 
+# Upgrade Python's YAML library
+python3 -m pip install --upgrade --ignore-installed PyYAML --user
+
 echo "Generating build_autogenerated.yaml from bazel BUILD file"
 rm -f build_autogenerated.yaml
 python3 tools/buildgen/extract_metadata_from_bazel_xml.py
diff --git a/tools/buildgen/mako_renderer.py b/tools/buildgen/mako_renderer.py
index f0202cd5ff9..06ee30ff2a3 100755
--- a/tools/buildgen/mako_renderer.py
+++ b/tools/buildgen/mako_renderer.py
@@ -15,28 +15,31 @@
 """Simple Mako renderer.
 
 Just a wrapper around the mako rendering library.
-
 """
 
 import getopt
-import imp
+import importlib.util
 import os
 import pickle
 import shutil
 import sys
 
+import yaml
 from mako.lookup import TemplateLookup
 from mako.runtime import Context
 from mako.template import Template
+
 import bunch
-import yaml
 
 
 # Imports a plugin
-def import_plugin(name):
-    _, base_ex = os.path.split(name)
-    base, _ = os.path.splitext(base_ex)
-    return imp.load_source(base, name)
+def import_plugin(path):
+    module_name = os.path.basename(path).replace('.py', '')
+    spec = importlib.util.spec_from_file_location(module_name, path)
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[module_name] = module
+    spec.loader.exec_module(module)
+    return module
 
 
 def out(msg):
@@ -104,7 +107,9 @@ def main(argv):
         elif opt == '-d':
             assert not got_preprocessed_input
             with open(arg, 'r') as dict_file:
-                bunch.merge_json(json_dict, yaml.load(dict_file.read()))
+                bunch.merge_json(
+                    json_dict,
+                    yaml.load(dict_file.read(), Loader=yaml.FullLoader))
         elif opt == '-p':
             plugins.append(import_plugin(arg))
         elif opt == '-w':
@@ -127,7 +132,7 @@ def main(argv):
     for arg in args:
         got_input = True
         with open(arg) as f:
-            srcs = list(yaml.load_all(f.read()))
+            srcs = list(yaml.load_all(f.read(), Loader=yaml.FullLoader))
         for src in srcs:
             if isinstance(src, str):
                 assert len(srcs) == 1