An operation processing device includes a first register unit including first registers configured to hold data to be used for an operation in an operation unit; a first selection unit that selects data held by a first register indicated by a read address signal; a second selection unit that selects, based on a bypass selection signal, data from a data group including the data selected by the first selection unit and data indicative of a result of the operation; a second register unit that outputs the data selected by the second selection unit to the operation unit; a timing adjustment unit that outputs the read address signal to the first selection unit; and a bypass control unit that stops an operation of the timing adjustment unit when generating the bypass selection signal indicative of a selection of data other than the data selected by the first selection unit.