To provide a method of manufacturing a crystal oscillator comprising a microminiaturized tuning fork flexural crystal vibrator with reduced frequency variations, even when miniaturization is attained, and to improve reliability and electrical characteristics, and a method of manufacturing an electronic device with the oscillator packaged therein.

Grooves 21, 27 are formed on upper surfaces of turning fork arms 20, 26 of a tuning fork flexural crystal vibrator 10, grooves are also formed on lower surfaces of the tuning fork arms 20, 26 similar to the upper surfaces, and electrodes are formed in the grooves and side surfaces opposite to the grooves. Since the grooves are formed after the tuning fork arms are formed, frequency variations due to manufacturing, with respect to a reference frequency, can be reduced; and since a frequency is adjusted after the electrodes are formed on the tuning fork arms, a frequency adjustment amount is reduced, such that a crystal oscillator, comprising a microminiaturized tuning fork flexural crystal vibrator that reduces frequency deviation, can be obtained. In addition, since the crystal oscillator is packaged in an electronic device, the electronic device comprising the crystal oscillator which reduces frequency deviation, with respect to the reference frequency, can be obtained at the same time.