diff --git a/pypdf/_cmap.py b/pypdf/_cmap.py
index f221d2d23..6efd028e7 100644
--- a/pypdf/_cmap.py
+++ b/pypdf/_cmap.py
@@ -121,6 +121,8 @@ def build_char_map_from_dict(
     "/GBpc-EUC-V": "gb2312",  # TBC
     "/GBK-EUC-H": "gbk",  # TBC
     "/GBK-EUC-V": "gbk",  # TBC
+    "/GBK2K-H": "gb18030",
+    "/GBK2K-V": "gb18030",
     # UCS2 in code
 }