Abstract: The soot accumulation at the surface of convection coil of heater occurred after it was put into operation for some time. Through analyzing the soot composition, causes of soot accumulation and the effect of soot accumulation on tube corrosion, technical requirements for high-pressure steam soot cleaning technology used in heater were put forward. Finally, a high-pressure steam soot cleaning system was developed. Based on the structure of convection chamber of heater, the high temperature steam pressure and temperature were selected as 0.7 MPa and 150℃, respectively. According to mechanical properties of the high temperature steam, manufacture processes and related calculation results, the burner structure was determined, and according to the width of convection chamber, the length of burner was chosen. Industrial application results of the above high-pressure steam soot cleaning system showed as follows: (1)reducing the average exhaust temperature(about 75~100 ℃), (2)improving the efficiency of heater(> 5%), (3)reducing the corrosion of the heater tube and(4)saving fuel.