Rheumatoid arthritis (RA) is a chronic disease of unknown etiology, characterized by synovitis of the diarthroidal joints, gradual bone erosion, and cartilage destruction. Temporomandibular joint (TMJ) arthritis is frequent in patients with RA, but it is seldom the first joint to be affected. This report presents a case of a female patient with undiagnosed RA who first presented with signs and symptoms of the disease in the TMJs. It highlights the importance of professional awareness and provides a roadmap for clinical and radiologic examination followed by biochemical and genetic monitoring for early diagnosis of RA.