diff --git a/packages/gatsby-remark-prismjs/README.md b/packages/gatsby-remark-prismjs/README.md
index d572012e37089..251076a157574 100644
--- a/packages/gatsby-remark-prismjs/README.md
+++ b/packages/gatsby-remark-prismjs/README.md
@@ -5,7 +5,7 @@ Adds syntax highlighting to code blocks in markdown files using
 
 ## Install
 
-`npm install --save gatsby-remark-prismjs`
+`npm install --save gatsby-transformer-remark gatsby-remark-prismjs`
 
 ## How to use