In this paper, the HL7702 cells were cured with 4% paraformaldehyde for different time durations. The atomic force microscope (AFM) and atomic force acoustic microscope (AFAM) were used to observe the surface and subsurface properties of the cured cells. The structures of the cells were changed with the curing time including the cytoskeleton, the shape, the height and the roughness of the cells. The lamellipodium can be seen for the curing time of 15 minutes with 4% paraformaldehyde. The optimal curing time was 15 minutes.This work provides a method for the study of cured cells in biomedicine.