To provide a pin boot for a disk brake capable of improving the salability.

In a pin boot 5 provided with a fitting part 5a to be fitted to a circumferential groove 3a of a slide pin 3, an expansion part 5b and a fit-in part 5c to be connected to a boss part 1a, the circumferential groove 3a is formed of a first annular grove part 3aa and a second annular groove part 3ab, and the fitting part 5a is provided with a body part 5aa, a lip part 5ab to be abutted on the first annular groove part 3aa, and an inward flange part 5ac to be abutted on the second annular groove part 5ab.