The invention relates to a positioning tool, a pasting system, a flexible circuit board, and a reinforced pasting method. The positioning tool comprises a first support plate and a second support plate, which are arranged in parallel at an interval and are movably connected with each other. The positioning tool also comprises a first positioning column, a second positioning column, and a positioning pin. One side, adjacent to the second support plate, of the first support plate is provided with a first shape groove and a first connection hole, which are communicated with each other. The firstshape groove is used for placing a reinforcing plate of a flexible circuit board. One side, adjacent to the first support plate, of the second support plate is provided with a second shape groove anda second connection hole, which are communicated with each other. The second shape groove is used for placing a board body of the flexible circuit board. The positioning tool, the pasting system, theflexible circuit board and the reinforced pasting method solve a problem that the coaxiality of an assembly hole in the flexible circuit board and the reinforcing hole in the reinforcing plate is poorer, effectively improve the reinforced pasting efficiency, and improves the assembly efficiency of the flexible circuit board.