Provided are crystals of 3-ethyl-4-{3-isopropyl-4-(4-(1-methyl-1H-pyrazol-4-yl)-1H-imidazol-1-yl)-1H-pyrazolo[3,4-b]pyridin-1-yl}benzamide which are stable and have excellent oral absorbability. The crystals are II-form crystals of 3-ethyl-4-{3-isopropyl-4-(4-(1-methyl-1H-pyrazol-4-yl)-1H-imidazol-1-yl)-1H-pyrazolo[3,4-b]pyridin-1-yl}benzamide which are characterized by giving an X-ray powder diffraction spectrum which has characteristic peaks at at least three diffraction angles (2?+0.20) selected from among 7.70, 8.00, 11.10, 12.50, 12.90, 15.20, 15.80, 17.20, 19.00, 22.50, 26.10, and 27.40.
