A　novel　technology　to　determine　the　concentration　of　hypoxanthine　through　the　chromogenic　reaction　of　phenic　acid　(PA),　4-aminoantipyrine　(AAP)　and　hydrogen　peroxide　(H2O2),　which　was　produced　via　the　oxidation　of　hypoxanthine　catalyzed　by　xanthine　oxidase　(XO),　under　the　help　of　horseradish　peroxidase　(HRP)　was　proposed　in　the　present　paper,　according　to　the　reaction　of　molybdoenzyme　xanthine　oxidase　(XOD,　EC　1.2.3.22)　which　mainly　catalyzes　the　conversion　of　hypoxanthine　and　xanthine　to　xanthine　and　uric　acid,　respectively,　and　is　capable　of　reducing　oxygen　to　generate　the　reactive　oxygen　species　(ROS),　superoxide　and　hydrogen　peroxide.　The　influences　of　temperature　and　pH　on　the　system　were　investigated.　The　optimal　conditions　to　determine　the　concentration　of　hypoxanthine　were　obtained　as　follows:　XO(0.32　UmL-1),　HRP(7.0UmL-1),　4-Aminoantipyrine(1　mmolL-1),　and　phenic　acid(6　mmolL-1)　were　dissolved　in　100　mmolL-1　Tris-HCl　buffer　solution　(pH　8.3),　and　the　reaction　system　was　incubated　in　thermostat　of　37C　for　8　min,　the　absorptive　wave　length　was　508　nm.　Under　the　conditions　mentioned　above,　the　linear　range　of　calibration　curve　was　between　0.2　and　3.0　mmolL-1,　the　correlation　coefficient　was　0.9979,　and　the　limit　of　detection　was　0.05　mmolL-1.　All　these　show　that　this　technology　is　a　potential　alternative　method　to　determine　the　concentration　of　hypoxanthine　in　areas　like　for　example　in　laboratory　or　clinical　serum　diagnosis.