Abstract: Disclosed are a bare cell, a cylindrical battery and an assembly method of the bare cell. The bare cell is formed a cylinder by stacking and winding a first electrode plate, a separator and a second electrode plate, the polarity of the first electrode plate is opposite to the polarity of the second electrode plate, at least one of the first electrode plate and the second electrode plate forms a plurality of tabs at at least one end of the cylinder in an axial direction, each of the plurality of tabs is provided with at least one die-cutting line to form a plurality of sub-tabs, the plurality of tabs are bent and flattened in a radial direction, and the plurality of sub-tabs of two adjacent layers of the plurality of tabs are arranged in a staggered manner.