Arthritis or arthritis is an inflammatory condition that causes inflammation of the joints occurs in and around joints. This inflammation causes the joints to swelling, stiffness characterized by pain. In May 2022 obtained data that the clinic provides health facilities including treatment general medical, acupuncture, and laboratory tests. Number of patients with a total of 32 patients and there is no arthritis specialist and only there is 1 doctor at the clinic who is scheduled to alternate with the schedule at home illness results in decreased efficiency of doctors in diagnosing. So that queue of visitors occurs which results in efficiency of visitor visits reduce. For this reason, an early diagnosis expert system was created with the results in the form of: supporting observation sheet for further physical examination so that the doctor in conducting medical practice and visitors in visits to clinics more efficient. The result of this study is the initial diagnosis of arthritis with highest probability. in each case shows that the level of manual calculation accuracy with 100% system calculation