Abstract: A fastener for a baby's diaper is provided which comprises a generally elastic base member having at least thre claw units spaced apart thereon. The base member can be resiliently extended and the claw units engaged with a cloth or fabric diaper to retain the two ends of the part thereof encircling a baby's waist in required relative positions and also to hold a portion passing between the baby's legs in position relative to the former. The claw units are specially designed to properly engage the fabric of a diaper and not to become dislodged therefrom (if properly installed) in use. The fastener obviates the use of conventional safety pins with the associated disadvantages and dangers.