Abstract: Based on the theory of chirped-pulse parametric amplification, the application of optical parametric amplification in chirped-pulse amplification is simulated. Gain and temporal characteristic of optical parametric chirped-pulse amplification is studied, especially in the small signal-condition and the large signal-condition. The infection of the group-velocity mismatch and the phase-velocity mismatch in the process of the amplification are discussed respectively. The request of synchronization between pump-pulse and signal-pulse is taked into account. The stability of the system is evaluated.