A process allocation apparatus includes an evaluation value calculating unit, an internode total communication traffic calculating unit, and a correction evaluation value calculating unit. The evaluation value calculating unit calculates an evaluation value of process allocation in accordance with a hop count and inter-process communication traffic from a communication source node to which a process used as a communication source is allocated to a communication destination node to which a process used as a communication destination is allocated. The internode total communication traffic calculating unit specifies a communication route from the communication source node to the communication destination node and calculates internode total communication traffic indicating that the communication traffic between nodes on the specified communication route. The correction evaluation value calculating unit calculates a correction evaluation value used for the correction in accordance with the calculated evaluation value of the process allocation and the calculated internode total communication traffic.