An oral preparation for treating cell proliferation diseases. The oral preparation comprises hydroxylpropoxyl-?cyclodextrin and an active component. The active component is KX2-361 or a medicinal salt thereof, and KX2-361 is represented by formula 1. By mixing hydroxylpropoxyl-ydcyclodextrin with KX2-361 or the medicinal salt thereof, an inclusion complex is formed, the solubility of the poorly-soluble drug KX2-361 is greatly improved, and accordingly the drug is prepared into an oral preparation. The oral preparation has good stability, high safety, good absorbability, high bioavailability and economical cost.