diff --git a/src/use-swr.ts b/src/use-swr.ts
index d769e8082..aca60c408 100644
--- a/src/use-swr.ts
+++ b/src/use-swr.ts
@@ -24,7 +24,8 @@ import {
   updaterInterface
 } from './types'
 
-const IS_SERVER = typeof window === 'undefined'
+// @ts-ignore
+const IS_SERVER = typeof window === 'undefined' || !!(typeof Deno !== 'undefined' && Deno && Deno.version && Deno.version.deno)
 
 // polyfill for requestAnimationFrame
 const rAF = IS_SERVER