The invention discloses a precise double-guide-rail net stretching device which comprises a support and angle body net stretching frames arranged on cross beams of the support. Vertical plates of the angle body net stretching frames are provided with guide screw sleeves. Screws fixedly connected with the cross beams of the supports are in screw joint in the guide screw sleeves. Adjusting hand wheels are arranged at the tail ends of the screws. Guide rails are arranged on cross plates of the angle body net stretching frames, wherein the two sides of each rail are opened. The guide rails are fixedly provided with multiple sets of supporting plates through sliding wheels. The upper portions of the supporting plates are fixedly provided with double-guide-rail screen net clamps through the support, and opposite suspension supporting plates are arranged on the opposite cross beams on the two sides of the support correspondingly. Synchronous air cylinders are arranged on the inner sides of the suspension supporting plates, U-shaped fixing seats are arranged at the top ends of lifting rods of the synchronous air cylinders, and net frame supporting rods are arranged between the opposite U-shaped fixing seats. According to the precise double-guide-rail net stretching device, it can be effectively ensured that a screen net does not deform, tensile force is even, net sticking is facilitated, the net stretching quality and efficiency can be greatly improved, and the precise double-guide-rail net stretching device is more suitable for large net plates and batched net loading.