A triglyceride enzyme sensor has been prepared by immobilizing lipase on pH glass electrode. The immobilized methods of lipase and the response characteristics of the sensor were studied.The linear range of detection is 3.09×10^－6～1.91×10^－3 mol/L for triglyceride with a slope of 32.7 mV/pC in the pH 8.5 Tris-HCl buffer solution at 37℃. The response time is 5～10 min. The sensor is relatively stable for 25 days.The sensor has been applied to the determination of triglyceride in serum with satisfactory results.