diff --git a/pyproject.toml b/pyproject.toml
index fade424..1abf697 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,7 +26,7 @@ torch = "^2.1.0"
 numpy = "^1.26.0"
 python-jose = {extras = ["cryptography"], version = "^3.3.0"}
 passlib = {extras = ["bcrypt"], version = "^1.7.4"}
-protobuf = "^6.33.0"
+protobuf = ">=6.33,<8.0"
 sentencepiece = "^0.2.1"
 httpx = "^0.25.0"
 cachetools = "^6.2.1"