Caspase is a rapidly growing family of aspartate-specific cysteine proteases(interleukin 1β-converting enzyme related proteases).Up to date,thirteen mammalian caspases have been discovered.Caspases normally exist in cells as inactive proenzymes.Caspases proteolytic processing at aspartate specific sites unleash their latent enzymatic activity and trigger cell apoptosis. Caspase as effector plays an important role in most cell apoptosis. Big progress was maded for the molecular mechanism of caspase activation and regulation in cell apoptosis.