Abstract: Based on SimPort simulation platform of nuclear power plant, a simulation model on the level control system of steam generator in the unit one of Qinshan Phase II NPP was established. Using this model, transient simulation experiments and researches with different conditions were conducted and the setpoints of the level control system were obtained. To level controller, K_P, T_I and T_D are 4.25, 425s and 10s respectively. To flow controller, K_P is 1.0 and T_I is 13s. These setpoints are in agreement with the actual values and can be referred by engineering technician.