Lead salt materials such as lead sulfide have attracted much attention in the field of uncooled infrared detection because of their low auger recombination coefficient. Chemical bath deposition method is widely used in the preparation of lead sulfide and other films. However, this method has the problem of uneven film growth on the graphical substrate. Based on the multi-exposure development technology, the influence of different pretreatment processes on the growth uniformity of the film on the graphical substrate was compared. The uniform growth of the lead sulfide film on the metal and insulating substrate surface was achieved. The results of the lead sulfide detector prepared by the optimal pretreatment method show that the photocurrent, responsivity and noise of the detector are significantly improved by the pretreatment of the graphic substrate, and the responsivity can be increased by 1.2 times. The preparation method of lead sulfide film provided in this paper can not only grow lead sulfide film with consistent uniformity on the graphic substrate, but also repair the damaged substrate, which is conducive to the integrated processing of the lead-sulfide-based focal plane array detector on the readout circuit surface.