Abstract: The four main production technologies，including conversion method of sodium nitrate and potassium chloride，ion exchange method of ammonium nitrate and potassium chloride，solvent extraction method of nitric acid and potassium chloride，and complex decomposition cycle method of ammonium nitrate and potassium chloride，of potassium nitrate both in China and abroad were summarized.The characteristics of these four different production technologies were compared.In the four kinds of production technologies，complex decomposition cycle method of ammonium nitrate and potassium chloride is the main production technology for potassium nitrate in China.Some major existing problems，such as poor separation effect of potassium nitrate，bad cooling crystallization effect of potassium nitrate，serious scaling of heat exchange surface of crystallizer，and bad purification，in this production technology were introduced emphatically.Furthermore，advices and measures for improving these problems were put forward.

Key words: potassium nitrate, production process, complex decomposition cycle method, improving measures