An image pickup apparatus capable of setting a shutter speed for moving image shooting up to a speed closer to a long exposure-side limit value irrespective of the setting exposure step increments for setting a shutter speed for still image shooting. Exposure step increments which values of a shutter speed can be set are set to one of a plurality of settings of exposure step increments according to a user's operation. A frame rate of a moving image to be shot is set in the moving image shooting mode. A shutter speed is set based on the set exposure step increments. In the moving image shooting mode, control is performed so as to make it possible to set a shutter speed which is the reciprocal of the set frame rate and does not conform to the set exposure step increments.