A parallel-serial conversion circuit including a data transmission unit to output first data and second data of a prescribed pattern in accordance with a second clock obtained by dividing a first clock, a first flip flop to receive the first data so as to output the first data in accordance with the first clock, a second flip flop to receive the second data so as to output the second data in accordance with the first clock, a selector to select one of the first data and the second data so as to output the selected data in accordance with the first clock, and an adjustment unit to compare the second data to be received by the second flip flop and the first data output from the first flip flop so as to adjust, based on a comparison result, a timing for the first flip flop to receive the first data.