The invention relates to a bifurcated-type flexible circuit board manufacturing method. By using the bifurcated-type flexible circuit board manufacturing method, before a first core plate and a secondcore plate are laminated, a through hole on a core plate separation area of the first core plate and a through hole of a core plate separation area of the second core plate are drilled, which is convenient for processing the core plate separation area through holes. When an internal layer graph of the first core plate and an internal layer graph of the second core plate are manufactured, an external layer graph of the core plate separation area of the first core plate and an external layer graph of the core plate separation area of the second core plate are manufacture so that a risk that theinternal layer graphs of the core plate separation areas are damaged can be avoided.