diff --git a/source/core/Ky.ts b/source/core/Ky.ts
index 9330a92d..a370b54d 100644
--- a/source/core/Ky.ts
+++ b/source/core/Ky.ts
@@ -169,7 +169,7 @@ export class Ky {
 
 		if (supportsAbortController) {
 			this.abortController = new globalThis.AbortController();
-			const originalSignal = this._options.signal || (this._input as Request).signal;
+			const originalSignal = this._options.signal ?? (this._input as Request).signal;
 			if (originalSignal) {
 				originalSignal.addEventListener('abort', () => {
 					this.abortController!.abort(originalSignal.reason);