This paper introduces the operation bottlenecks of condensate recovery system in the 220 kt/a ethylene plant of PetroChina Dushanzi Petrochemical Company. Through technical investigation, design optimization and implementation of technical measures, the operation bottlenecks of condensate recovery system are eliminated, the industrial condensate is further recovered and reused, and the goal of green factory without odor is achieved. Through minor modifications in local areas, the operation efficiency of the upstream and downstream units of the ethylene plant is improved, and the production cost is reduced.