The output power of the mid-infrared solid-state laser based on nonlinear frequency conversion technology,which is limited by the back conversion effect,is relatively low due to the damage threshold and coating process of the optical crystal,and the optical parametric amplification technology can effectively solve this problem.In the paper,the typical structure and characteristics of optical parametric amplification technology and common optical crystals are introduced.The latest development of optical parametric amplification technology to increase the output power of nanosecond mid-infrared solid-state laser is reviewed.Scientific challenges of optical parametric amplification technology in increasing nanosecond mid-infrared solid-state laser output power are also analyzed.