diff --git a/index/li/libgmp/libgmp-external.toml b/index/li/libgmp/libgmp-external.toml
index 3b6bd5cb..8d16e595 100644
--- a/index/li/libgmp/libgmp-external.toml
+++ b/index/li/libgmp/libgmp-external.toml
@@ -10,6 +10,7 @@ kind = "system"
 "debian|ubuntu" = ["libgmp-dev"]
 arch = ["gmp"]
 msys2 = ["mingw-w64-x86_64-gmp"]
+homebrew = ["gmp"]
 
 [[external]]
 kind = "version-output"