A method for manufacturing a flexible circuit board includes providing a first laminated structure, the first laminated structure including two first wiring boards, a first adhesive layer sandwiched between the two first wiring boards, and a first conductive structure. The first conductive structure penetrates the two first wiring boards and the first adhesive layer and electrically connects the two first wiring boards. The first adhesive layer defines a first opening, the first opening includes a first edge away from the first conductive structure. The first laminated structure is cut along the first edge and then the two first wiring boards are unfolded. A flexible circuit board manufactured by such method is also disclosed.