The invention discloses a crystal of flumatinib mesylate, the process for preparing the crystal, and composition comprising therapeutic amount of the crystal, and used for treating chronic myelogenous leukemia thereof. The crystal disclosed in this invention is crystal C. The crystal C disclosed in this invention shows good stability and solubility, and it’ s very favorable for pharmaceutical composition.本發明公開了一種甲磺酸氟馬替尼晶型及其製備方法，以及含有治療有效量的該晶型醫藥組成物及其在治療慢性髓性白血病中的應用，本發明公開的是一種甲磺酸氟馬替尼晶型C。本發明所提供的甲磺酸氟馬替尼晶型C具有較好的穩定性和溶解性，且對醫藥組成物非常有利。
