The invention discloses a manufacturing method of a bidirectional fiber Bragg grating, a bidirectional tracer and a passive network. The manufacturing method comprises the steps as follows: laser is irradiated on a mask area of a phase mask plate, so that the laser to expose an optical fiber via the mask area, so as to form a first chirp grating and a second chirp grating on the optical fiber; thefirst chirp grating and the second chirp grating have the same central wavelength and chirp rate; the grating period of the first chirp grating is gradually increased from one end of the optical fiber to the other end of the optical fiber; the grating period of the second chirp grating is gradually increased from the other end of the optical fiber to one end of the optical fiber, and the gratingperiod of the first chirp grating and the grating period of the second chirp grating are symmetrically distributed on the optical fiber. The bidirectional tracer can be acquired via the abovementionedmanufacturing method. The passive network comprises the bidirectional tracer. According to the method, tracer and network provided by the invention, the flexibility and operability of optical link detection are increased.