diff --git a/ironic/api/types.py b/ironic/api/types.py
index b022e50a3a..55b26ab0eb 100644
--- a/ironic/api/types.py
+++ b/ironic/api/types.py
@@ -142,12 +142,12 @@ class BinaryType(UserType):
     def tobasetype(self, value):
         if value is None:
             return None
-        return base64.encodestring(value)
+        return base64.encodebytes(value)
 
     def frombasetype(self, value):
         if value is None:
             return None
-        return base64.decodestring(value)
+        return base64.decodebytes(value)
 
 
 #: The binary almost-native type
diff --git a/ironic/tests/unit/api/test_types.py b/ironic/tests/unit/api/test_types.py
index fb39ff2b77..d61825cf4d 100644
--- a/ironic/tests/unit/api/test_types.py
+++ b/ironic/tests/unit/api/test_types.py
@@ -446,13 +446,13 @@ Value: 'v3'. Value should be one of: v., v.",
     def test_binary_to_base(self):
         import base64
         assert types.binary.tobasetype(None) is None
-        expected = base64.encodestring(b'abcdef')
+        expected = base64.encodebytes(b'abcdef')
         assert types.binary.tobasetype(b'abcdef') == expected
 
     def test_binary_from_base(self):
         import base64
         assert types.binary.frombasetype(None) is None
-        encoded = base64.encodestring(b'abcdef')
+        encoded = base64.encodebytes(b'abcdef')
         assert types.binary.frombasetype(encoded) == b'abcdef'
 
     def test_wsattr_weakref_datatype(self):