Selective determination of uric acid (UA) was conducted in the presence of ascorbic acid (AA) and acetaminophen (APAP) as interference species at an unmodified glassy carbon paste electrode (GCPE). Using the GCPE prepared in our lab, we succeeded in detecting UA in the presence of AA in acidic and alkaline media. In addition, the oxidation peak potential of APAP is very close to that of UA in neutral media, but in alkaline media, a peak separation of ca. 140mV was obtained between UA and APAP on the differential pulse voltammogram (DPV).