A memory system includes a non-volatile memory, a data buffer in which data read out from the nonvolatile memory are stored prior to transmission to an initiator that is requesting the data, a port through which the initiator sends a request for the data and through which the data in the data buffer are transmitted to the initiator. When the port is connected to a first initiator at a time both first data requested by the first initiator and second data requested by a second initiator are stored in the data buffer and the second data become ready for transmission prior to the first data, the second data are transmitted through the port prior to the first data.