The present invention belongs to the field of medicinal chemistry. Specifically, the present invention relates to a crystal A and a crystal B of a pyrrolopyrimidine compound (formula I) as a JAK inhibitor, a method for producing the crystal A and the crystal B, and a crystal composition containing the crystal A or the crystal B , A crystal composition containing crystal A or crystal B or a crystal composition thereof, and a pharmaceutical use thereof. Crystal A and crystal B according to the present invention have advantages such as high purity, high crystallinity, and good stability. [Chemical 1] [Selected figure] None本発明は医薬化学分野に属する。具体的には、本発明は、ＪＡＫ阻害剤としてのピロロピリミジン化合物（式Ｉ）の結晶Ａ及び結晶Ｂに関し、さらに前記結晶Ａ及び結晶Ｂの製造方法、前記結晶Ａ又は結晶Ｂを含む結晶組成物、前記結晶Ａ又は結晶Ｂ又はその結晶組成物を含む医薬組成物、並びにそれらの医薬用途に関する。本発明に係る結晶Ａ及び結晶Ｂは、純度が高く、結晶度が高く、安定性が良い等の利点を有する。【化１】【選択図】なし
