diff --git a/python/sglang/srt/environ.py b/python/sglang/srt/environ.py
index e3ad080f3..fa802f44d 100644
--- a/python/sglang/srt/environ.py
+++ b/python/sglang/srt/environ.py
@@ -1265,7 +1265,7 @@ class Envs:
     SGLANG_OPT_USE_TILELANG_MHC_PRE = EnvBool(True)
     SGLANG_OPT_USE_TILELANG_MHC_POST = EnvBool(True)
     SGLANG_OPT_USE_FLASHINFER_MHC = EnvBool(False)
-    SGLANG_OPT_FUSE_MHC_POST_PRE = EnvBool(False)
+    SGLANG_OPT_FUSE_MHC_POST_PRE = EnvBool(True)
     SGLANG_OPT_USE_TILELANG_INDEXER = EnvBool(False)
     SGLANG_OPT_DSV4_NONPAGED_INDEXER = EnvBool(True)
     # Per-rank local query rows (after DP-attention sharding when enabled),