The invention provides an on-off monitoring structure of a bending connected pipeline. The structure comprises an oil-gas separator, an intake manifold and a bending connected pipeline, wherein the bending connected pipeline is connected between the oil-gas separator and the intake manifold; a guide wire is buried in the bending connected pipeline; the two ends of the guide wire are connected to apower source to form a closed loop; if current is detected in the closed loop, the bending connected pipeline is judged to be connected well; and if current is not detected in the closed loop, the bending connected pipeline is judged to be disconnected. Due to the fact that the guide wire is buried in the pipe wall of the bending connected pipeline and the two ends of the guide wire are connectedto the power source to form the closed loop, if the bending connected pipeline is connected, current can be detected in the closed loop; if the bending connected pipeline is disconnected, the guide wire is disconnected, the closed loop becomes an open circuit, current cannot be detected in the closed loop, thus the bending connected pipeline is judged to be disconnected. The on-off monitoring structure of the bending connected pipeline can be used for monitoring on-off of the bending connected pipeline.