The invention discloses a PCB conveying mechanism, and belongs to the technical field of circuit board conveying. The PCB conveying mechanism comprises a bearing seat, a feeding mechanism, a conveyingseat, a corner mechanism, a turnover mechanism, a conveying frame, a fixing mechanism, a dust collecting mechanism, a discharging mechanism and a discharging box; the conveying seat is arranged beside the bearing seat, and a conveying belt is arranged on the conveying seat; a moving groove is formed in the side wall of the conveying seat, the corner mechanism is arranged on the conveying seat, the turnover mechanism is arranged on the conveying seat, the conveying frame is arranged on the conveying seat, the fixing mechanism is arranged on the conveying seat, the dust collecting mechanism isarranged beside the conveying seat, and the discharging mechanism is arranged beside the conveying seat; and the discharging box is arranged beside the discharging mechanism. According to the PCB conveying mechanism, the feeding mechanism is adopted for feeding step by step, meanwhile, circuit boards are rotated and turned over in the conveying process, and the circuit boards can be machined conveniently in the conveying process.