diff --git a/package.json b/package.json
index 0085c77..9002b37 100644
--- a/package.json
+++ b/package.json
@@ -56,7 +56,7 @@
         "@babel/register": "^7.4.4",
         "@webcomponents/webcomponentsjs": "^2.2.10",
         "babel-eslint": "^10.0.1",
-        "bootstrap": "4.2.1",
+        "bootstrap": "4.3.1",
         "esdoc": "^1.1.0",
         "esdoc-ecmascript-proposal-plugin": "^1.0.0",
         "esdoc-external-webapi-plugin": "^1.0.0",