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Protected horticulture industry has developed rapidly in China in recent years. With the continuous development, a series of problems have arisen, which resulted in a huge loss in protected horticulture industry. For example, simplifying varieties, high multiple crop index and fertilizer overspending can lead to terrible results on the soil, like salts accumulation, disorder of soil physical and chemical properties, soilborn disease and insects, autotoxicity of crops, and so on, which called continuous cropping obstacle. The preferred manner to deal with continuous cropping obstacle is soil steam disinfection because of its great advantages compared with chemical disinfection. For example, with high temperature steam as disinfection medium, it can ensure that no pesticide residue on food. Besides, it can also effectively regulate soil physical and chemical properties, improve soil respiration ability and prevent soil hardening. To solve the problem of steam supply in soil steam disinfestation, a steam generator based on pulse combustion technology was designed. The power of 107.12kW was needed when the yield of the steam generator was 130kg/h with the pressure of 0.6MPa. It was mainly composed of two parts: the pulse combustion engine and the pot body. The steam generator utilized four pulse combustion engines which worked in parallel, and the main parts were immersed in the water in the pot body. Each pulse combustion utilized two carburetors for oil and air supply, which were connected to combustion chamber with “Y”shaped throat. Three helical tubes worked in parallel as tailpipe. Fins were adhered to the inner wall of decoupling chamber, and angel steel was adhered to the outer wall. Experiment results showed that the pulse combustion engine had great start-up performance and working stability both in the air and water. The working frequency was tested both in the air and water. The working frequency of pulse combustion engine in the air was kept between 90.80Hz and 90.89Hz, and the average frequency was 90.86Hz. In the water, the working frequency of pulse combustion engine was kept between 87.27Hz and 87.81Hz, and the average frequency was 87.51Hz. The thermal efficiencies of the steam generator under the rated and non-rated operating conditions were 95.5% and 95.8% respectively, and the difference was less than 0.3%. Under the rated operating conditions, steam production, oil consumption and power of the steam generator were 150kg/h, 9.7kg/h, 110.8kW, respectively. Besides, tail gas temperature and excess air coefficient were 108℃ and 1.026, respectively. The steam generator can meet the requirement of steam in soil steam disinfection quite well. The research provided a reference for the research and development of the soil steam disinfection machine used in protected horticulture industry.