Pegomastax ("strong jaw") is a genus of heterodontosaurid dinosaur discovered in Lower Jurassic rocks in South Africa. It is based on SAM-PK-K10488, a partial skull including a postorbital bone, both dentaries (the tooth-bearing bone of the lower jaw), and a predentary (a toothless beak-like bone found at the tip of the lower jaw). From head to tail the parrot-like herbivore measured no more than 60 cm.