In order to solve the problem of comprehensive ecological management of the Daihai Sea in China, Inner Mongolia Autonomous Region has planned and implemented the project of diverting Yellow River to Daihai, however, due to the fact that the Yellow River diversion water is a micro-polluted surface water with nitrate nitrogen as the main pollutant, which has the characteristics of carbon and nitrogen ratio, DO high water quality, the sulphur autotrophic denitrification is a major technology that is expected to solve the problem at the present time. In this study, in order to strengthen the effect of nitrogen removal, coconut shell activated carbon, sulfur and limestone were used as the activated carbon enhanced sulfur autotrophic denitrification substrate package (ASL) and coupled with MBBR balls to form the ASL-MBBR process, the nitrogen nitrogen removal effects of four ASL-MBBR processes with different activated carbon percentages were investigated and compared with a blank control scheme. The results of the study showed that: 1 MBBR ball containing 18g of autotrophic denitrification substrate package was placed in 2L of experimental water under the following Under the conditions of, the four experimental protocols with the mass ratios of coconut shell activated carbon:sulfur:limestone in the substrate package were 1:1:1, 2:1:1, 3:1:1, 4:1:1, and the removals of TN were 66.40%, 60.19%, 71.36%, and 73.02%, respectively; and the removals of NO3-N were 83.20%, 79.74%, and 87.01%, respectively, 88.08%. Among them, Scheme 4 with a mass ratio of 4:1:1 had the best nitrogen removal. This research result is expected to provide a new and more effective technology for nitrogen removal in solving the problem of micro-polluted surface water with high dissolved oxygen.