diff --git a/package.json b/package.json
index eefde26..638969b 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "babel-preset-stage-0": "^6.24.1",
     "jest": "^21.2.1",
     "makeshift": "^1.1.0",
-    "mobx": "^3.4.1",
+    "mobx": "^5.15.1",
     "rimraf": "^3.0.0",
     "semistandard": "^14.0.1"
   },
@@ -54,6 +54,6 @@
     "@parity/shared": "^3.0.1"
   },
   "peerDependencies": {
-    "mobx": "^3.4.1"
+    "mobx": "^5.15.1"
   }
 }
diff --git a/yarn.lock b/yarn.lock
index bc8af58..1a18985 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3170,9 +3170,9 @@ mobx@2.6.4:
   version "2.6.4"
   resolved "https://registry.yarnpkg.com/mobx/-/mobx-2.6.4.tgz#e05a91a5b2c97dac3fdab34024e6b74a7f4311ab"
 
-mobx@^3.4.1:
-  version "3.4.1"
-  resolved "https://registry.yarnpkg.com/mobx/-/mobx-3.4.1.tgz#37abe5ee882d401828d9f26c6c1a2f47614bbbef"
+mobx@^5.15.1:
+  version "5.15.1"
+  resolved "https://registry.yarnpkg.com/mobx/-/mobx-5.15.1.tgz#ba07807808b3f9dc3e6b0a74ba69bcccc6df4ece"
 
 ms@2.0.0:
   version "2.0.0"