diff --git a/Lib/lib2to3/pgen2/tokenize.py b/Lib/lib2to3/pgen2/tokenize.py
index d14db60f7da89ea..213a72624d85065 100644
--- a/Lib/lib2to3/pgen2/tokenize.py
+++ b/Lib/lib2to3/pgen2/tokenize.py
@@ -95,9 +95,10 @@ def maybe(*choices): return group(*choices) + '?'
 Token = Ignore + PlainToken
 
 # First (or only) line of ' or " string.
-ContStr = group(r"[uUbB]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*" +
+_litprefix = r"(?:[uUrRbBfF]|[rR][bB]|[bBuU][rR])?"
+ContStr = group(_litprefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*" +
                 group("'", r'\\\r?\n'),
-                r'[uUbB]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*' +
+                _litprefix + r'"[^\n"\\]*(?:\\.[^\n"\\]*)*' +
                 group('"', r'\\\r?\n'))
 PseudoExtras = group(r'\\\r?\n', Comment, Triple)
 PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name)
@@ -108,11 +109,14 @@ def maybe(*choices): return group(*choices) + '?'
             "'''": single3prog, '"""': double3prog,
             "r'''": single3prog, 'r"""': double3prog,
             "u'''": single3prog, 'u"""': double3prog,
+            "f'''": single3prog, 'f"""': double3prog,
             "b'''": single3prog, 'b"""': double3prog,
             "ur'''": single3prog, 'ur"""': double3prog,
             "br'''": single3prog, 'br"""': double3prog,
+            "rb'''": single3prog, 'rb"""': double3prog,
             "R'''": single3prog, 'R"""': double3prog,
             "U'''": single3prog, 'U"""': double3prog,
+            "F'''": single3prog, 'F"""': double3prog,
             "B'''": single3prog, 'B"""': double3prog,
             "uR'''": single3prog, 'uR"""': double3prog,
             "Ur'''": single3prog, 'Ur"""': double3prog,
@@ -120,29 +124,39 @@ def maybe(*choices): return group(*choices) + '?'
             "bR'''": single3prog, 'bR"""': double3prog,
             "Br'''": single3prog, 'Br"""': double3prog,
             "BR'''": single3prog, 'BR"""': double3prog,
+            "rB'''": single3prog, 'rB"""': double3prog,
+            "Rb'''": single3prog, 'Rb"""': double3prog,
+            "RB'''": single3prog, 'RB"""': double3prog,
             'r': None, 'R': None,
             'u': None, 'U': None,
+            'f': None, 'F': None,
             'b': None, 'B': None}
 
 triple_quoted = {}
 for t in ("'''", '"""',
           "r'''", 'r"""', "R'''", 'R"""',
           "u'''", 'u"""', "U'''", 'U"""',
+          "f'''", 'f"""', "F'''", 'F"""',
           "b'''", 'b"""', "B'''", 'B"""',
           "ur'''", 'ur"""', "Ur'''", 'Ur"""',
           "uR'''", 'uR"""', "UR'''", 'UR"""',
           "br'''", 'br"""', "Br'''", 'Br"""',
-          "bR'''", 'bR"""', "BR'''", 'BR"""',):
+          "bR'''", 'bR"""', "BR'''", 'BR"""',
+          "rb'''", 'rb"""', "Rb'''", 'Rb"""',
+          "rB'''", 'rB"""', "RB'''", 'RB"""',):
     triple_quoted[t] = t
 single_quoted = {}
 for t in ("'", '"',
           "r'", 'r"', "R'", 'R"',
           "u'", 'u"', "U'", 'U"',
+          "f'", 'f"', "F'", 'F"',
           "b'", 'b"', "B'", 'B"',
           "ur'", 'ur"', "Ur'", 'Ur"',
           "uR'", 'uR"', "UR'", 'UR"',
           "br'", 'br"', "Br'", 'Br"',
-          "bR'", 'bR"', "BR'", 'BR"', ):
+          "bR'", 'bR"', "BR'", 'BR"',
+          "rb'", 'rb"', "Rb'", 'Rb"',
+          "rB'", 'rB"', "RB'", 'RB"',):
     single_quoted[t] = t
 
 tabsize = 8
diff --git a/Misc/NEWS b/Misc/NEWS
index 299a8388ff6e39d..d3a99f90fe07735 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -29,6 +29,8 @@ Library
   exception) to exception(s) raised in the dispatched methods.
   Patch by Petr Motejlek.
 
+- bpo-23894: lib2to3 now parses rb'...' and f'...' strings.
+
 
 What's New in Python 3.6.1 release candidate 1
 ==============================================