diff --git a/CHANGES.rst b/CHANGES.rst
index db20805..829f6f5 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,3 +1,9 @@
+v3.5.2
+======
+
+#39: Replace use of deprecated ``base64.encode/decodestring``
+with ``encode/decodebytes``.
+
 v3.5.1
 ======
 
diff --git a/keyrings/alt/Windows.py b/keyrings/alt/Windows.py
index a9bb45b..dd77220 100644
--- a/keyrings/alt/Windows.py
+++ b/keyrings/alt/Windows.py
@@ -91,7 +91,7 @@ def get_password(self, service, username):
             password_saved = winreg.QueryValueEx(hkey, username)[0]
             password_base64 = password_saved.encode('ascii')
             # decode with base64
-            password_encrypted = base64.decodestring(password_base64)
+            password_encrypted = base64.decodebytes(password_base64)
             # decrypted the password
             password = _win_crypto.decrypt(password_encrypted).decode('utf-8')
         except EnvironmentError:
@@ -103,7 +103,7 @@ def set_password(self, service, username, password):
         # encrypt the password
         password_encrypted = _win_crypto.encrypt(password.encode('utf-8'))
         # encode with base64
-        password_base64 = base64.encodestring(password_encrypted)
+        password_base64 = base64.encodebytes(password_encrypted)
         # encode again to unicode
         password_saved = password_base64.decode('ascii')
 
diff --git a/keyrings/alt/file_base.py b/keyrings/alt/file_base.py
index 0cb2c14..e7552a0 100644
--- a/keyrings/alt/file_base.py
+++ b/keyrings/alt/file_base.py
@@ -2,24 +2,14 @@
 
 import os
 import abc
-import base64
 import configparser
+from base64 import encodebytes, decodebytes
 
 from keyring.errors import PasswordDeleteError
 from keyring.backend import KeyringBackend
 from keyring.util import platform_, properties
 from .escape import escape as escape_for_ini
 
-try:
-    encodebytes = base64.encodebytes
-except AttributeError:  # pragma: no cover
-    encodebytes = base64.encodestring
-
-try:
-    decodebytes = base64.decodebytes
-except AttributeError:  # pragma: no cover
-    decodebytes = base64.decodestring
-
 
 class FileBacked(object):
     @abc.abstractproperty
diff --git a/keyrings/alt/pyfs.py b/keyrings/alt/pyfs.py
index 16c06f5..1610634 100644
--- a/keyrings/alt/pyfs.py
+++ b/keyrings/alt/pyfs.py
@@ -171,7 +171,7 @@ def get_password(self, service, username):
         try:
             password_base64 = self.config.get(service, username).encode()
             # decode with base64
-            password_encrypted = base64.decodestring(password_base64)
+            password_encrypted = base64.decodebytes(password_base64)
             # decrypted the password
             password = self.decrypt(password_encrypted).decode('utf-8')
         except (configparser.NoOptionError, configparser.NoSectionError):
@@ -188,7 +188,7 @@ def set_password(self, service, username, password):
         password_encrypted = self.encrypt(password.encode('utf-8'))
 
         # encode with base64
-        password_base64 = base64.encodestring(password_encrypted).decode()
+        password_base64 = base64.encodebytes(password_encrypted).decode()
         # write the modification
         if not self.config.has_section(service):
             self.config.add_section(service)