This paper proposes a task transmission control with dynamic lightpath setup in an optical grid. In our proposed method, a job manager changes the number of tasks in a resource manager dynamically so as to maintain a constant processing delay. It leads to effective utilization of computing resource. I-PD control is applied to maintain efficient network management. Furthermore, in order to avoid frequent lightpath setup process, multiple lightpaths are established simultaneously by our proposed algorithm. Numerical results show the effectiveness of the proposed task transmission method. (c) 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.