A circuit device includes: a first terminal and a second terminal coupled to a resonator; an amplifier circuit configured to amplify a signal from the first terminal and output the amplified signal to the second terminal; a variable resistance circuit that is provided on a signal path between the amplifier circuit and the second terminal and includes a variable resistor, a first switch provided at one end of the variable resistor, and a second switch provided at the other end of the variable resistor; a third switch coupled in parallel to the variable resistance circuit; and a control circuit configured to control a resistance value of the variable resistor and control the first switch, the second switch, and the third switch to be turned on or off.