diff --git a/README.md b/README.md
index 99a7734..542e126 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 
 ## Install
 
+Make sure you have OCaml >= 4.03.
+
    opam install batteries lens ppx_deriving omd opium tyxml ptime re
    git clone git@github.com:orbifx/logarion.git
    cd logarion