Abstract: In order to obtain the structure of electromagnetic boiler heater with maximum heat exchange efficiency, five parameters of heater are selected as the design parameters, these are, heating rod diameter, heating rod uniform distribution diameter, heating rod uniform distribution angle, non-metallic shell inner wall diameter and non-metallic shell wall thickness. Based on the multi-physical field coupling calculation, the response surface model and genetic algorithm are used to optimize the design parameters of the heater; and then the structural parameters with the highest efficiency are obtained. The heat transfer efficiency of the optimized heater reach to 97.8%, which is 5.8% higher than that of the prototype heater structure.