In the space-ground integrated network (SGIN), the deployment of multi-controllers has become a key factor affecting the efficiency of the control and management. In order to adapt to the control delay and resource constraints requirements of SGIN, this paper studies the multi-controller deployment problem considering control delay and load balance. We make the following contributions. First, we evaluate the average network response delay of low-orbit satellite nodes based on the satellite network topology and satellite network resource status. Furthermore, the load balance is considered in the proposed model to satisfy the resource constraints of SGIN. Second, a new heuristic algorithm is proposed to effectively improve the convergence speed of searching feasible solutions based on the improved immune algorithm. Third, the proposed method is numerically demonstrated considering a simulated SGIN architecture based on STK.