A crystalline form of (R) -4-hydroxy-2-oxo-1-pyrrolidineacetamide is disclosed. The crystal type has a diffraction angle 2θ of 16.66 ± 0.2 °, 17.54 ± 0.2 °, 21 ± 0.2 °, 22.16 ± 0.2 ° or 30.96 ± 0.2 °. And has a diffraction peak. The crystalline form has a solubility of 90 mg / mL or more, can be readily dissolved in water, is characterized by high bioavailability, has high stability at high temperatures, and is suitable for the preparation of multiple pharmaceutical compositions, tablets Multiple dosage forms such as capsules, drop pills, sustained release formulations, controlled release formulations, lyophilized powder injections and the like can be prepared. The method for preparing the crystal form is carried out under loose conditions, easy to operate, has few impurities in it, has good reproducibility, can easily control the production process, has high safety and is suitable for industrial production. Is suitable.（Ｒ）－４－ヒドロキシ－２－オキソ－１－ピロリジンアセトアミドの結晶型が開示される。結晶型は、回折角度２θが１６．６６±０．２°、１７．５４±０．２°、２１±０．２°、２２．１６±０．２°または３０．９６±０．２°であるとき、回折ピークを有する。結晶型は、９０ｍｇ／ｍＬ以上の溶解度を有し、水にすぐに溶解でき、高いバイオアベイラビリティを特徴とし、高温で高い安定性を有し、複数の医薬組成物の調製に適しており、錠剤、カプセル、滴丸剤、徐放性製剤、制御放出製剤、凍結乾燥粉末注射剤などの複数の剤型を調製できる。結晶型を調製するための方法は、緩い条件下で実行され、操作が容易であり、入り込む不純物が少なく、再現性が良く、生産プロセスを容易に制御でき、安全性が高く、工業的生産に適している。
