Background: Allopurinol is a drug that is widely used to treat hyperuricemia, but it is often prescribed inappropriately. Objective: The authors conducted a study to look for the appropriate allopurinol prescription and diagnosis of gout in the out-patient clinics at a university hospital. Material and Method: One hundred and forty-five patients who were newly prescribed allopurinol (128 males and 17 females, mean ± SD age of 58.5 ± 14.1 years) were enrolled in this study. Result: Only 77 (53.1%) received allopurinol with appropriate indications. Thirty-eight patients (26.2%) did not have allopurinol dose adjustment according to the patients' creatinine clearance. Among 131 patients, prescribed allopurinol for the diagnosis of gout, only 55 (42.0%) were diagnosed in accordance with the American Rheumatism Association criteria. Conclusion: Inappropriate use of allopurinol (both the indication and prescribed dosage) and inappropriate diagnosis of gout are major problems even in a large teaching hospital. An educational campaign program is warranted for achieving appropriate diagnosis of gout, and eliminating the inappropriate use of allopurinol.