diff --git a/Cargo.toml b/Cargo.toml
index f428ccd01..853f19d5c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ repository = "https://github.com/ebfull/ff"
 
 [dependencies]
 byteorder = "1"
-rand_core = "0.3"
+rand_core = "0.4"
 ff_derive = { version = "0.3.0", path = "ff_derive", optional = true }
 
 [features]