Pseudoxanthoma elasticum (PXE) is a rare, inherited disorder of the connective tissue. Possible association of autoimmune thyroiditis and PXE has been suggested, but reports of other autoimmune diseases complicating PXE are rare. We report a case of rheumatoid arthritis (RA) in a patient with PXE. Since the frequency of PXE is likely to be underdiagnosed, further studies to elucidate the true incidence and significance of the association of RA and PXE will be needed.