diff --git a/lib/internal/worker.js b/lib/internal/worker.js
index 48886aee3fef5d..702806e427c4ef 100644
--- a/lib/internal/worker.js
+++ b/lib/internal/worker.js
@@ -216,7 +216,7 @@ class Worker extends EventEmitter {
     this[kDispose]();
     if (customErr) {
       debug(`[${threadId}] failing with custom error ${customErr} \
-        and with reason {customErrReason}`);
+        and with reason ${customErrReason}`);
       this.emit('error', new errorCodes[customErr](customErrReason));
     }
     this.emit('exit', code);