BACKGROUND & OBJECTIVE The interest on the occurrence multidrug resistance and pathogenicity of Aeromonas hydrophila is increasing worldwide since it causes gasteroenteritis to children. Though reports on the occurrence of gasteroenteritis among children due to A. hydrophila in Tamil Nadu are available from certain areas, no information is available from Coimbatore. Hence, this study was undertaken to find out the occurrence of the pathogenic A. hydrophila in diarrhoeal stool of children, particularly in Coimbatore region. METHODS Isolation and identification of A. hydrophila was carried out from stool samples collected from children with acute diarrhoea. Multiple antibiotic resistance was determined by disc diffusion method. The pathogenicity of A. hydrophila was confirmed by production of haemolysin, protease and slime. RESULTS Of the 216 samples, 21 (9.7%) were positive for A. hydrophila. Among them 20 isolates were resistant to bacitracin. Most of the isolates showed multiple antibiotic resistance. Among the 21 isolates, protease and haemolysin producers were 100 and 95 per cent respectively. About 76 per cent of the isolates produced slime. INTERPRETATION & CONCLUSION The results of the present study indicated the presence of pathogenic A. hydrophila in the study area causing diarrhoea among children.