Provided is an improved method for stereoselectively preparing 2′-deoxy-2′,2′-difluorocytidine of formula (I), which includes reacting a 1-halo ribofuranose compound with a nucleobase of formula (IV) in a solvent to obtain a nucleo side of formula (II) with removal of a silyl halide ((alkyl)3SiX (X=halide)); and deprotecting the nucleoside of formula (II) to obtain 2′-deoxy-2′,2′-difluorocytidine of formula (I). 2′-Deoxy-2′,2′-difluorocytidine of formula (I) is effective for treating various cancers such as non-small cell lung (NSCLC), pancreatic, bladder, breast or ovarian cancers.