The cat eye echo detection system of optical imaging system in the process of CCD damage was established. The data of cat eye echo power and degree of polarization of optical imaging system during CCD damage process were recorded and the curve of change was drawn. The change mechanism of cat eye echo characteristics, the relationship between CCD damage state and the change of cat eye echo power and degree of polarization were analyzed. The results show that there is no good correlation between the change of cat eye echo power and degree of polarization and the change of CCD damage state during the process of point damage, line damage and full target damage of CCD detector in optical imaging system by pulsed laser irradiation. The CCD is completely damaged when the first pulse is irradiated by increasing the damage laser energy. In the 0-8 pulse damage process, the cat eye echo power and degree of polarization increase first, then decrease, then increase and finally decrease, which can be used to judge whether CCD is completely damaged.