To provide a C/V conversion circuit that has a small number of components, and that does not require the adjustment of the resistance value of a resistor, and to provide an acceleration sensor that uses the C/V conversion circuit.

A switched capacitor circuit 11 is constituted in such a way that at leas two switches 131, 132 are connected to a variable-capacitance capacitor 12, as an object to be measured, inside a C/V conversion circuit 1, in which a value expressing the capacitance of a capacitor is converted into a voltage at a prescribed C/V conversion rate. The C/V conversion rate is constituted so as to be decided according to the ratio of the equivalent resistance value of the switched capacitor circuit 11 to the resistance value of a resistance circuit 15. When the ON-OFF frequency of the switches 131, 132 is controlled, the equivalent resistance value of the switched capacitor circuit 11 can be changed, and the C/V conversion rate can be adjusted. It is possible to obtain an accelerometer in which a later-stage amplifier is not required and in which the adjustment of a voltage amplification factor by a resistance timing operation or a resistance short circuit is not required.