The present invention relates to a crystalline form of a co-crystal of an inhibitor against sodium-glucose cotransporter 2 with L-proline, a method for preparing the same, a pharmaceutical composition comprising the same, and use thereof. Specifically, the present invention relates to a crystalline form of a co-crystal of an inhibitor against sodium-glucose cotransporter 2 represented by formula (1), i.e., (2S,3R,4R,5S,6R)-2-(3-(4-(((1R,3s,5S)-bicyclo[3.1.0]hexan-3-yl)oxy)benzyl)-4-chlorophenyl)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol, with L-proline, a method for preparing the same, a pharmaceutical composition comprising the same, and use thereof.