PURPOSE: To provide the temperature compensation type oscillator whose FM noise characteristic is improved.

CONSTITUTION: The oscillator consists of a crystal oscillator circuit 35, a temperature detector circuit 21 outputting temperature information as an N-bit 1st digital signal 22, converter circuits 23, 25 outputting a Q-bit 2nd digital signal 26 based on the 1st digital signal 22, and a frequency adjustment circuit 39 adjusting an oscillating frequency of the crystal oscillator circuit 35 based on the 2nd digital signal 26. The bit number N of the 1st digital signal 22 is decided so that a maximum value of a change in the oscillating frequency at the minimum temperature resolution of the temperature detector circuit 21 is 1Hz or below, and a change in the operating frequency adjusted by the 2nd digital signal 26 in one-bit is featured to be 1Hz or below.