To prevent a through current due to signal fixation cancellation before supplying power, by stabilizing a signal state in reset cancellation when starting power supply in a power controllable circuit, in a power consumption reduction circuit of LSI having the power controllable circuit.

There are provided: a masking circuit 6 for fixing an input signal 4 to the power controllable circuit 1 and an input signal 3 from the circuit 1 to a regularly powered circuit 2 by a control signal 5 during power cutoff of the circuit 1; a delay circuit 7 for delaying the control signal 5; a reset masking circuit 10 for fixing a reset signal 9 to the circuit 1 by the output of the delay circuit 7 during the power cutoff of the circuit 1; and a control signal masking circuit 12 for fixing the control signal 5 by a state signal 11 representing a power supplying state of the circuit 1.