Described herein is a cable-type secondary battery having a horizontal cross section of a predetermined shape and extending longitudinally, comprising: a core for supplying lithium ions, which comprises an electrolyte; an inner electrode surrounding the outer surface of the core for supplying lithium ions, and comprising an inner current collector in the form of a pipe having a three-dimensional network structure, the inner current collector being coated with an inner electrode active material on the outer surface thereof; a separation layer surrounding the outer surface of the inner electrode to prevent a short circuit between electrodes; and an outer electrode surrounding the outer surface of the separation layer and comprising an outer electrode active material layer and an outer current collector.