PURPOSE: To adjust the temperature characteristic precisely and readily by measuring the frequencies of main and secondary quartz oscillators at three points of a temperature range in a constant temperature chamber and calculating the correction values from said measured values.

CONSTITUTION: A quartz watch 310 is set in the constant temperature chamber wherein the temperature can be set in the range of -10W60°C. The paces of the main and secondary quartz oscillators of said crystal watch are measured by a frequency or period counter 320 at the three temperatures T1WT3. By using said measured data, an operating device 330 performs a specified operation, and obtains the adjusting parameters and the correction values for the paces of the main and secondary oscillators. Based on said correction values, the temperature characteristic of the pace of the quartz watch is corrected. Thus temperature characteristic of the quartz watch can be adjusted precisely and readily.