PURPOSE: To provide the clinical thermometer which can accurately measure the temperature of a drum membrane for a short time and the clinical thermometer evaluation device used for the aforesaid clinical thermometer.

CONSTITUTION: Substantial infrared rays from the drum membrane are continuously detected at specified intervals by an infrared ray sensor 10 provided for the inside of a probe section 5, and they are operated by a control section 15 through a filter amplifier 14 and an A/D converter 14 so as to be made the values of temperature. A peak value of temperature is judged as follows: the operated peak value of temperature is held at a memory section 16, and is compared with the value of temperature measured one after another by a comparison means, when the measured one is found greater than the operated peak value, the operated peak value is renewed, and it is stored in the memory section 16. The peak value found through a regular number of measurements is compared with the aforesaid renewed value, and when no renewal is found, measurement is to be ended with the operated peak value made to be the maximum temperature, and a display drive section 17 is driven so as to allow the peak value to be indicated on a display section 2. Data corrected by an external evaluation device is written from an external input/output section 20 so as to be corrected.