Objective To develop a monitoring implement of body temperature in hyperthermia.It can display the result of body temperature and send out alarm to protect the security of patients according to the reference in hyperthermia.Methods To test the body temperature by using temperature sensor.The body temperature is displayed finally by LCD through signal disposed by linearity and amplification.It also can be disposed by AD converter and chip microprocessors.Results The implement can check the body temperature under the error of ±1% in hyperthermia.Conclusion The implement can measure the body temperature accurately and continuously at the real time in hyperthermia.