Abstract: When CCD detectors damaged by nanosecond pulsed laser, with the deepening of damage degree, the phenomena of point damage, white line damage and complete failure appear successively in the output pictures of the imaging system, and the damage thresholds exhibit a nature of probability distribution. The laser wavelength was 1 064 nm in our experiment. At first, the CCD detectors were illuminated with n-on-1 mode, three different degrees of damage behaviors were observed, and the damage mechanism was analyzed on basis of the working principle of the CCD imaging system. The damage morphology of the samples were studied with an optical microscope, and it is found that the damage initiates from the inner part of the detectors and then spreads to the micro-lens structure on the surface. Next, the irradiation mode of 1-on-1 was employed to measure the damage thresholds for the degree of point damage and system failure. The former is expressed in the way of probability distribution, and the thresholds of system failure are around 100 mJ/cm2.