An image pickup apparatus arranged to perform a focus adjustment by moving a focus lens based on an image pickup signal, parallelly reading out the image pickup signal obtained in a period set by a timing signal for setting a first exposure period and the image pickup signal obtained in a period set by a timing signal for setting a second exposure period from an image pickup unit by shifting the timing signals from each other in phase, obtain a focus evaluation value from the image pickup signal obtained in the set exposure period, and determine a position of the focus lens corresponding to the focus evaluation value based on a focus lens position when the image pickup signal is read out for the first exposure period and a focus lens position when the image pickup signal is read out for the second exposure period.