Objective: To identify the monoclonal antibody specific to Aeromonas spp., a Gram negative bacteria causing gastroenteritis and wound infection. Methods: The monoclone, namely 88F2-3F4, was produced from hybridoma technology. The specificity of antibody secreted from 88F2-3F4 was tested against other Gram negative bacteria frequently found in gastrointestinal tract. Then the antibody was used for searching Aeromonas antigens in artificial seeded rectal swab cultures by dot-blot enzyme linked immunosorbent assay. Results: 88F2-3F4 produced an antibody that recognized an antigen with a molecular mass of 8.5 kDa in all 123 isolates of the seven Aeromonas species tested, but recognized no epitope of any other Gram-negative bacterium typically found in the gastrointestinal tract. A dot-blot enzyme linked immunosorbent assay based on this antibody showed 86.49% sensitivity and 92.13% specificity. Conclusions: 88F2-3F4 monoclonal antibody could react with all Aeromonas isolates, but not other Gram negative bacteria, therefore it should be a useful tool for the detection of Aeromonas antigen in clinical and environmental samples.