An image pickup apparatus that can reduce power consumption of the image pickup apparatus, and take high-definition moving images at high speed without bringing about decreases in recordable time and the number of still images taken. An image pickup processing unit is operated in a plurality of operation modes, and has an image pickup device and a plurality of processing units that process image pickup signals outputted from the image pickup device. An interval control circuit causes the image pickup processing unit to switch between a standby ON state and a standby OFF state in predetermined timing. A control signal is outputted to the interval control unit according to an operation mode of the image pickup processing unit. When the image pickup processing unit lies in a predetermined operation mode, a control signal for causing the interval control circuit to perform the switching is outputted to the interval control circuit.