A flexible printed circuit board includes a main flexible board and a bridging flexible board, wherein the main flexible board includes a first main pad, a second main pad, a first signal line and a second signal line, and the bridging flexible board includes a first bridging pad and a second bridging pad; the first main pad includes at least two first solder joints, the second main pad includes at least two second solder joints, the first bridging pad includes at least two third solder joints, and the second bridging pad includes at least two fourth solder joints.