The invention discloses a fiber-like-structured lithium ion battery and a preparation method. The fiber-like-structured lithium ion battery is a complete lithium ion battery and has all performance ofthe battery, and also can be used as a reinforcing body of a composite material so as to obtain a force-bearing structured board in a composite manner. The dimension of fiber battery is in a millimeter level, so that the battery is different from the common lithium ion battery; and the battery with the structure has relatively high specific energy density and charging rate as well as relatively high mechanical strength. The preparation method of the fiber-structured battery comprises the steps of 1) selecting positive electrode current collector metal fibers; 2) coating the surface with a positive electrode active material; 3) packaging by a diaphragm; 4) winding with negative electrode fibers (carbon fibers); and 5) performing wetting of a dual-continuous-phase electrolyte and curing.