Abstract: Objective To lay the foundation for establishing a morphological structure database of commonly used antibodies by studying the morphology of antigen-antibody reaction under atomic forced microscope. Methods Seven antibodies were added onto slides and placed into a wet kit containing 10% neutral buffer formalin. One hour after the antibodies were kept in an incubator at 37 ℃, they were washed with distilled water and dried. Their morphologies were observed under atomic force microscope. The width, maximum height and mean roughness of particles were measured. Results The long rod cytokeratin and S100 protein muse anti-human monoclonal antibodies, the oblate round common antigens of vimentin and leukocyte as well as cytokeratin 7 and Dog-1 mouse antihuman monoclonal antibodies, and the triangle thyroglobulin monoclonal antibodies were observed in 2D figures. The width and maximum height of monoclonal antibodies were significantly different (P< 0.05), but no significant difference was found in the mean roughness (P> 0.05). Conclusion The morphologies of 7 monoclonal antibodies can be divided into long rod, oblate round and triangle types, which directly prove the relative specificity of antibodies and can thus provide the morphological foundation for further studying the co-expression and exceptional expression of antigens.