the task of med ical diagnosis, unlike other diagnostic processes is more comp lex because a lot of vagueness, linguistic uncertainty, subjectivity, measurement imprecision, natural diversity are all prominently present in medical d iagnosis . Osteoarthritis (OA) of the knee is a majo r public health issue causing chronic disability and reduction in quality of life; it is reported to be associated with a significant decline in function and causes a higher rate of disability than any other chronic condition. Osteoarthritis (OA) exacts a cost in terms of pain, limited mobility, and decreased function among a wide range of ind ividuals. With improvement in science and technology, intelligent computing has been used to assist in enhancing qualitative services. This paper reports the development of a fu zzy-based system to determine the level of severity of knee osteoarthritis, given some input conditions. The system was imp lemented and simulated using MATLAB Fu zzy Logic Toolbo x. The results are entrusting and promising based on the flexibility and case of adaptability.