A hose clamp includes a plate spring main body, and a slit and a first grip piece are formed at one end portion, while an insertion piece and a second grip piece are formed at the other end portion thereof. A locking piece having a hook-shaped locking portion is formed on the first grip piece via a bent portion, while an engagement holding portion is formed on the second grip piece. Provided on the locking piece are a taper portion which expands from the locking portion towards the bent portion and a stopper portion which extends substantially parallel to the first grip piece. The taper portion is disposed along a plane which is substantially parallel to a circumferential surface of the plate spring main body, and an intersection point between the taper portion and the stopper portion is offset in a width direction relative to the locking portion.