A distributed memory multiprocessor system including a plurality of cells interconnected via an inter-cell network, each of the plurality of cells including at least one cache, a memory, a memory controller, and a directory managing a status of data stored in the memory, the distributed memory multiprocessor system includes a directory information updating unit of a first cell that updates the directory of the first cell, and a directory information transmitting unit of a second cell that transmits the directory information contained in the directory of the second cell. The directory information transmitting unit of the second cell transmits the directory information, which is read out from the directory of the second cell, to the first cell. And, the directory information updating unit of the first cell receives the directory information transmitted by the directory information transmitting unit of the second cell and updates the directory of the first cell.