A MEMS oscillator including: an oscillator unit being capable of outputting an output from an amplifier as an original oscillator signal that includes a feedback type oscillator circuit including a MEMS resonator and an amplifier, and an automatic gain controller receiving the output from the amplifier and controlling a gain of the amplifier based on a level of the output to maintain a level of the output from the amplifier constant; and a corrector unit that receives the original oscillator signal, that generates from the original oscillator signal a signal of a predetermined set frequency, and that outputs the generated signal of the predetermined set frequency as an output signal. The corrector unit receives, separately from the original oscillator signal, an information signal that includes a signal having a correspondence relationship between a gain at a resonance frequency of the MEMS resonator from the oscillator unit, corrects a frequency of the original oscillator signal based on the information signal to generate the signal of the predetermined set frequency, and outputs the generated signal of the predetermined set frequency as the output signal.