Abstract: The loss in the storage and transportation system of ethylene chemical plant is one of the total energy losses for the petrochemical enterprises.Evaporation loss of storage tank, loading loss of products, loss of tank cleaning and leakage loss of products are the major causes of product loss in storage and transportation system.Combined with the system loss in Fushun Ethylene Chemical Plant, the paper presents various measures to reduce the product loss, also analyzes the loss of flare system and steam and puts forward some relevant control measures.