To provide a container holder that can be positively and easily fitted to a handle stem, a handlebar, or the like of a bicycle and can cope with beverage holders of various sizes by providing a storage part with an elastic side plate.

A beverage container holder is composed of a grip part formed of a clamping piece, a abutting piece or the like fitted to a handle stem B1 of a bicycle, a beverage container accommodating storage part 1 formed of an elastic side plate, elastic holding legs 115, or the like provided at the grip part so as to be able to hold a beverage container firmly, and a locking body such as a set screw B4 or a fastener provided at the handle stem with which a bottom plate 113 of the storage part is brought into contact. The storage part 1 is prevented from being rotated by the clamping piece, and prevented from falling off by the bottom plate and the locking body.