[Problem] Provided is a pharmaceutical composition which suppresses gelation of the 7-{(3S,4S)-3-[(cyclopropylamino)methyl]-4-fluoropyrrolidine-1-yl}-6-fluoro-1-(2-fluoroethyl)-8-methoxy-4-oxo-1,4-dihydroquin oline-3-carboxylic acid hydrochloride and which suppresses elution delay. [Solution] This solid pharmaceutical composition is obtained by using crystals (B-form crystals) of a hydrate of 7-{(3S,4S)-3-[(cyclopropylamino)methyl]-4-fluoropyrrolidine-1-yl}-6-fluoro-1-(2-fluoroethyl)-8-methoxy-4-oxo-1,4-dihydroquin oline-3-carboxylic acid hydrochloride, having peaks at 9.4 and 17.7 degrees (±0.2 degrees for each angle) as 2¸ diffraction angles in X-ray powder diffraction using CuK± emission.
