To provide a delay circuit improved in the accuracy of a delay time. A delay circuit is provided which includes a plurality of switches respectively provided between a plurality of constant current sources and a delay time adjustment terminal, a control circuit which ON/OFF-controls the switches, and a comparator circuit which compares a voltage of the delay time adjustment terminal and a reference voltage. The control circuit sequentially turns ON the switches every preset period after a signal is inputted to a signal input terminal and sets as a delay time, a time taken for the comparator circuit to detect that the voltage of the delay time adjustment terminal exceeds the reference voltage.