This paper presents the research that the addition of inorganic alkali and activated carbon has a great influence on the refining process of crude guanidine nitrate.After the study on various process parameters,the purification conditions are:92%of crude product nitrate guanidine was dissolved in the water temperature of 90℃~100℃for about 1 h,and 0.030%~0.035%activated carbon was added to the mixture.After cooling,0.030%inorganic alkali was added at 40.0℃under constant stirring,purified and dehydrated after 5 h of crystallization,the content of nitrate guanidine can reach about 98.5%,basically reaching the standard of excellent grade.