diff --git a/lib/deno/mod.ts b/lib/deno/mod.ts
index a0eed9f2260..c3553e032c0 100644
--- a/lib/deno/mod.ts
+++ b/lib/deno/mod.ts
@@ -52,6 +52,7 @@ let initializeWasCalled = false
 export const initialize: typeof types.initialize = async (options) => {
   options = common.validateInitializeOptions(options || {})
   if (options.wasmURL) throw new Error(`The "wasmURL" option only works in the browser`)
+  if (options.wasmModule) throw new Error(`The "wasmModule" option only works in the browser`)
   if (options.worker) throw new Error(`The "worker" option only works in the browser`)
   if (initializeWasCalled) throw new Error('Cannot call "initialize" more than once')
   await ensureServiceIsRunning()
diff --git a/lib/npm/node.ts b/lib/npm/node.ts
index eee195e6c58..6eddae2c621 100644
--- a/lib/npm/node.ts
+++ b/lib/npm/node.ts
@@ -226,6 +226,7 @@ let initializeWasCalled = false;
 export let initialize: typeof types.initialize = options => {
   options = common.validateInitializeOptions(options || {});
   if (options.wasmURL) throw new Error(`The "wasmURL" option only works in the browser`)
+  if (options.wasmModule) throw new Error(`The "wasmModule" option only works in the browser`)
   if (options.worker) throw new Error(`The "worker" option only works in the browser`)
   if (initializeWasCalled) throw new Error('Cannot call "initialize" more than once')
   ensureServiceIsRunning()