Abstract: On site tests are carried out by means of adding pour depressant to achieve under-capacity operation for Wei-Jing Pipeline. The tests are made by adding oil-diluted depressant GY-3 into pipeline with a concentration of 50×10^-6 at a raised temperature of 70℃. The results show a pour point decrease of 7℃ from 37℃ to 30℃, a viscosity reduction of 76% from 260 mPa·s to 62. 0 mPa·s at 35℃ and a shear rate of 529 s^-1, an abnormal point drop of 13℃ from 43℃ to 30℃, and a throughput reduction from 5000 t/d to 2500 t/d. Discussed are the impact of repeatative heating on additive performance and the influence of the coming oil with a lower pressure on wax deposit. Economical analysis shows that depressant is more economic than reverse pumping to reduce flow rate. Some suggestion are given for adding depressant.