diff --git a/mix.exs b/mix.exs
index f48c3ec..71b09c9 100644
--- a/mix.exs
+++ b/mix.exs
@@ -61,7 +61,7 @@ defmodule Minecraft.MixProject do
       {:inch_ex, only: :docs},
       {:mock, "~> 0.3.0", only: :test},
       {:ranch, "~> 1.5"},
-      {:poison, "~> 3.1"}
+      {:poison, "~> 4.0"}
     ]
   end
 
diff --git a/mix.lock b/mix.lock
index 22508b6..9ecba54 100644
--- a/mix.lock
+++ b/mix.lock
@@ -17,7 +17,7 @@
   "mock": {:hex, :mock, "0.3.2", "e98e998fd76c191c7e1a9557c8617912c53df3d4a6132f561eb762b699ef59fa", [:mix], [{:meck, "~> 0.8.8", [hex: :meck, repo: "hexpm", optional: false]}], "hexpm"},
   "nimble_parsec": {:hex, :nimble_parsec, "0.5.0", "90e2eca3d0266e5c53f8fbe0079694740b9c91b6747f2b7e3c5d21966bba8300", [:mix], [], "hexpm"},
   "parse_trans": {:hex, :parse_trans, "3.3.0", "09765507a3c7590a784615cfd421d101aec25098d50b89d7aa1d66646bc571c1", [:rebar3], [], "hexpm"},
-  "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm"},
+  "poison": {:hex, :poison, "4.0.1", "bcb755a16fac91cad79bfe9fc3585bb07b9331e50cfe3420a24bcc2d735709ae", [:mix], [], "hexpm"},
   "ranch": {:hex, :ranch, "1.7.1", "6b1fab51b49196860b733a49c07604465a47bdb78aa10c1c16a3d199f7f8c881", [:rebar3], [], "hexpm"},
   "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.4", "f0eafff810d2041e93f915ef59899c923f4568f4585904d010387ed74988e77b", [:make, :mix, :rebar3], [], "hexpm"},
   "unicode_util_compat": {:hex, :unicode_util_compat, "0.4.1", "d869e4c68901dd9531385bb0c8c40444ebf624e60b6962d95952775cac5e90cd", [:rebar3], [], "hexpm"},