A wavelength converting apparatus comprising: a laser resonator; a first wavelength converting element that converts a fundamental wave outputted from the laser resonator into a harmonic wave; a first temperature control element that controls the temperature of the first wavelength converting element; a second wavelength converting element that converts a fundamental wave outputted from the first wavelength converting element into a harmonic wave; a second temperature control element that controls the temperature of the second wavelength converting element; a first detecting portion that detects an output of a harmonic wave outputted from the first wavelength converting element; a second detecting portion that detects an output of a harmonic wave outputted from the second wavelength converting element; and a controller that manages temperature control of the first wavelength converting element by the first temperature control element, temperature control of the second wavelength converting element by the second temperature control element, and current value control of a driving current applied to the laser light source.