The invention provides a flexible circuit board. The circuit connection area and the non-functional area adjacent to the circuit connection area are arranged on the flexible circuit board, so that thecombination of a chip and the circuit connection area is realized. Furthermore, a hollow area is arranged in the non-functional area; therefore, one part of the chip can cover the hollow area, thereby improving heat dissipation of the chip, moreover, a reinforcing sheet is arranged on the back surface of the non-functional area; good support strength and a flat surface are provided for the combination of the chip and the flexible circuit board, the combination capability of the chip and the flexible circuit board is improved, the combination interface of the chip and the flexible circuit board is improved, the heat dissipation capability of the chip is also improved, and the corrosion resistance of the combination interface of the flexible circuit board and the chip is also improved. Dueto the design of the hollow area of the non-functional area, the reinforcing sheet can be in direct contact with the chip to improve the heat dissipation capability, thereby prolonging the service life of the chip on the flexible circuit board and improving the performance of the whole device.