The present invention relates to a CPT-bound compound or a pharmaceutically acceptable salt thereof, the CPT-bound compound being obtained by binding CPT (or a CPT derivative) and guanidine to a reduced monosaccharide. The CPT-bound compound enhances solubility and cell permeability of the CPT drug, which makes it possible to effectively deliver CPT to target cells. Therefore, a pharmaceutical composition comprising, as an active ingredient, the CPT-bound compound or a pharmaceutically acceptable salt thereof is expected to be able to effectively treat cancer, in particular, colorectal cancer, even with a low dose of CPT.