A plurality of command storage areas respectively corresponding to a plurality of priorities and storing I/O commands in a storage control apparatus are common to a plurality of ports and a plurality of processors. Here, regardless of which port receives an I/O command, the I/O command is stored in a command storage area corresponding to a priority which is given to the I/O command. The plurality of processors run the I/O commands in the plurality of command storage areas so that an I/O command with a higher priority is run more often within a given period of time.