Abstract: Based on the design of Chinese Spallation Neutron Source (CSNS) target station neutron beam extraction pipes, shielding efficiency was evaluated using the two-dimensional discrete ordinates transport code DORT for different design models. Two-dimensional dose field distribution and the axial distribution were calculated. Meanwhile, an optimal shielding model was obtained from the calculation. The model ensures that the received doses of the hall staff members below the required standard limit. The results show that the shielding model inserted with SS316 steel has a better shielding efficiency than that without SS316 steel. In addition, the model of the shutter front with tungsten plate has a better efficiency than the others. The shielding efficiency of the vary length tungsten plate was discussed.