A fine-patterning method includes forming a mask layer with lower and upper mask layers on an underlying layer, forming a pair of sacrificial patterns on the mask layer, forming a connection spacer between the sacrificial patterns and first spacers that are spaced apart from each other with the pair of sacrificial patterns interposed therebetween and covering side surfaces of the sacrificial patterns, etching the upper mask layer using the first spacers and the connection spacer as an etch mask to form upper mask patterns, forming second spacers to cover side surfaces of the upper mask patterns, etching the lower mask layer using the second spacers as an etch mask to form lower mask patterns, and etching the underlying layer using the lower mask patterns as an etch mask.