PURPOSE: To obtain an electronic clinical thermometer which is easy to use and high in accuracy by such an arrangement wherein it is composed so that a display informing a certain period of waiting time from the beginning of measurement can be indicated and the measurement of the highest temperature can be started at such a point of time at which an oscillating circuit has been stabilized.

CONSTITUTION: It is composed so that a first oscillating circuit is kept driven even when the temperature of a body is not measured, but a second oscillating circuit 2 is driven only when the temperature of a body is measured. Control signals necessary for the measurement of the temperature of a body are produced by a timing controller 1 which uses the output signal of the first oscillating circuit 1 as an input signal. The detection of a body temperature is performed by counting the output signal 1 of an AND circuit G1 which uses the output signal 1 of the timing controller 3 and the output signal 2 of the second oscillating circuit 2 as an input with a counter 4. The output of the counter 4 is once latched by a latch 5 and then displayed on a display unit 7 by a decoder-driver 6. The AND circuit G2 controls whether the output data of the counter 4 is to be read into the latch 5 or not.