In animal veterinary practice, dermatological diseases in cats are one of the most commonly reported cases. This paper presents Feline Dermatology Expert System (FEDES), a rule-based Veterinary Medical Expert System for diagnosis of feline dermatological disease. It captures the expertise's knowledge, which is then organized and represented by rules contained in the system's knowledge base. These rules are analyzed by the expert system's inference engine to output a diagnosis and its corresponding explanation. The prototype of the system is developed in client-server based architecture and taken on for verification and validation. Results show that FEDES is able to perform effectively in diagnosis of feline dermatological disorders as diagnosed by veterinarians.