The invention discloses a guide bar device of a warping machine. The guide bar device comprises a main device frame, square guide bar apparatuses are clamped to the top and the bottom of the main device frame, first horizontal rods are fixedly connected to the front of the main device frame, and main frame connecting clamps are fixedly connected to the side face of the main device frame; main frame vertical rods are in bolted connection with the sides, away from the main device frame, of the main frame connecting clamps, main frame fixing bases are in bolted connection with the bottoms of themain frame vertical rods, second horizontal rods are in bolted connection with the tops of the main frame connecting clamps, and transmission idler wheels are rotatably connected to the ends, away from the main frame connecting clamps, of the second horizontal rods. According to the guide bar device, the square guide bar apparatuses are staggered at the top and bottom of the main device frame, yarn is distributed into two paths, the arrangement density of the yarn is lowered on the condition that the number of strands of the yarn is not reduced, it is guaranteed that the yarn is not easily knotted or tangled, the working efficiency of the warping machine is improved, and each square guide bar apparatus can be independently detached, so that maintenance is facilitated.