A low power flip-flop includes first to fourth signal generation circuits and an inverter. The first signal generation circuit receives the clock signal, the data input signal, and a first internal signal that is an output of the second signal generation circuit and generates a second internal signal. The inverter receives the first internal signal and generates an inverted first internal signal. The second signal generation circuit receives the first internal signal and the output signal that is an output of the third signal generation circuit, and generates the inverted output signal. The third signal generation circuit receives the clock signal and the inverted output signal and generates the output signal. The fourth signal generation circuit receives the inverted first internal signal, the second internal signal, and the clock signal and generates the first internal signal.