A clinical and radiological study was performed in forty patients (male 10, female 30) with onset of definite or classical RA over 60 years. There were no statistically significant differences in the sex ratio, positive rate of latex fixation test (85%), distribution of affected joints, efficacy of treatments and prognosis between the elderly-onset and ordinary rheumatoid patients described previously. However, complications such as renal dysfunction and pulmonary fibrosis were higher. More careful use of long-term drug therapy may be essential for these elderly patients. The degree of radiographic changes, evaluated by Larsen's grade, showed no correlation with the sex, latex fixation test or Lansbury's index. However, the patients who had an increased erythrocyte sedimentation rate (over 30 mm/hour), a higher amount of plasma IgM and a longer duration of illness (over 5 years) showed significantly higher Larsen's grades. Single photon absorptiometry (Norland Model 278) both of the distal one third and one sixth of the radius, showed that the former correlated more highly with Larsen's grade than the latter.