This invention relates to a crystal oscillation circuit that oscillates stably with a low power consumption. This crystal oscillation circuit comprises an inverting amplifier, a crystal oscillator, and a feedback circuit that inverts the phase of an output from this inverting amplifier and feeds it back as an input. The sum of the absolute value of the threshold voltage of a first semiconductor switching element and the absolute value of the threshold voltage of a second semiconductor switching element is set to be greater than or equal to the absolute value of the potential difference between first and second potentials, when said inverting amplifier includes the first and second semiconductor switching elements.