diff --git a/Cargo.toml b/Cargo.toml
index 60bb817..50f3176 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "patricia_tree"
-version = "0.5.5"
+version = "0.5.6"
 authors = ["Takeru Ohta <phjgt308@gmail.com>"]
 description = "Memory-efficient data structures based on patricia tree"
 homepage = "https://github.com/sile/patricia_tree"