The invention providesa crystal form A of 3(2-acetylamino-acetylamino)-propionic acid、its preparing method and application thereof. The crystal form A of 3(2-acetylamino-acetylamino)-propionic acid has higher purity, excellent thermal stability and is applied in the skin whitening area. The crystal form A of 3(2-acetylamino-acetylamino)-propionic acidis obtained by re-crystallization from an alcohol solvent and the re-crystallization method is easy to operate and well control.本發明是關於一種用於抑制黑色素生成的化合物3(2-乙醯胺基-乙醯胺基)-丙酸的晶型A及其製備方法和應用。本發明提供的化合物3(2-乙醯胺基-乙醯胺基)-丙酸的晶型A的純度高,熱穩定性佳並應用於非治療用途的皮膚美白。且本發明所提供的製備方法是使用低毒性的醇類溶劑,其條件溫和,並且可以獲得高純度和再現性好的3(2-乙醯胺基-乙醯胺基)-丙酸的晶型A。
