The present invention relates to N- n-propyls -3- (4- aminomethyl phenyls) -4- (4- methanesulfonylphenYls) -2,5- pyrrolin -2- ketone I types crystallization and preparation method thereof. This method include by any crystal form or unformed N- n-propyls -3- (4- aminomethyl phenyls) -4- (4- methanesulfonylphenYls) -2,5- pyrrolin -2- ketone solid polar organic solvent or their aqueous crystallization obtain N- n-propyls -3- (4- aminomethyl phenyls) -4- (4- methanesulfonylphenYls) -2,5- pyrrolin -2- ketone I types crystallize. Obtained N- n-propyls -3- (4- the aminomethyl phenyls) -4- (4- methanesulfonylphenYls) -2 of the present invention,The crystallization of 5- pyrrolin -2- ketone I types has good stability of crystal form and chemical stability, and recrystallisation solvent low toxicity and low residue used, can preferably use what clinical treatment.本發明涉及N-正丙基-3-(4-甲基苯基)-4-(4-甲磺酰基苯基)-2,5-二氫吡咯-2-酮I型結晶及其製備方法。該方法包括將任意晶型或無定型的N-正丙基-3-(4-甲基苯基)-4-(4-甲磺酰基苯基)-2,5-二氫吡咯-2-酮固體用極性有機溶劑或者它們的水溶液結晶得到N-正丙基-3-(4-甲基苯基)-4-(4-甲磺酰基苯基)-2,5-二氫吡咯-2-酮I型結晶。本發明所得到的N-正丙基-3-(4-甲基苯基)-4-(4-甲磺酰基苯基)-2,5-二氫吡咯-2-酮I型結晶具備良好的晶型穩定性和化學穩定性，並且所用結晶溶劑低毒低殘留，可更好地用於臨床治療。
