diff --git a/lib/ecto/adapters/mysql.ex b/lib/ecto/adapters/mysql.ex
index 5a14e5ce02..be6132d186 100644
--- a/lib/ecto/adapters/mysql.ex
+++ b/lib/ecto/adapters/mysql.ex
@@ -106,6 +106,8 @@ defmodule Ecto.Adapters.MySQL do
     do: [&json_decode/1, &Ecto.Adapters.SQL.load_embed(type, &1)]
   def loaders(_primitive, type), do: [type]
 
+  defp bool_decode(<<0>>), do: {:ok, false}
+  defp bool_decode(<<1>>), do: {:ok, true}
   defp bool_decode(0), do: {:ok, false}
   defp bool_decode(1), do: {:ok, true}
   defp bool_decode(x), do: {:ok, x}