Introduction: Diarrhoea is still a major killer of under five children in India. Mothers are the main care takers of children andto reduce the morbidity and mortality due to diarrhoea, they should have correct knowledge regarding prevention and control of childhood diarrhoea. Therefore the present study was conducted among mothers of under five children to assess their knowledge about prevention and control of diarrhea. Methodology: A cross sectional study was conducted among 115 mothers of under five children who had visited a teaching hospital (study setting) during study period. Data was collected by interviewing the mothers with the help of pre designed questionnaire. Data was analyzed by appropriate statistical techniques. results: Approximately half of the participants had (50.4%) average knowledge, 24.3% had poor knowledge level. Only 46% of mothers were knowing at least one cause of diarrhea and unclean water was the most common cause perceived by them. 71% mothers heard about ORS and health workers was the main source of information for them. Conclusion: The knowledge was average and significantly better among educated women.