Cattle diseases namely anaplasmosis, anthrax, babesiosis, black quarter, brucellosis, foot and mouth disease, haemorrhagic septicaemia, infectious bovine rhinotracheitis, leptospirosis, mastitis, theileriosis and trypanosomiasis. The thirteen cattle diseases and their clinical signs or symptoms were identified based on the information available and provided by the veterinarians and experts in the field. A questionnaire was prepared for marking the different scores for various signs or symptoms of thirteen cattle diseases. The questionnaire was tested for face and content validity and for reliability. The scoring of signs or symptoms for thirteen cattle diseases were collected from field veterinarians. The Aiken’s value index was calculated for the cattle disease signs or symptoms. The weighted matrix was developed for various clinical signs or symptoms for the cattle diseases. Based on this, the expert system was developed in the form of web application or computer programme. The expert system was validated internally for diagnosis of cattle diseases.