The lack of rapid and effective on-line detection means for combine screw conveyor leads to poor machining quality, which leads to material blockage, blade open welding, excessive wear between blade and shell. In order to solve the problem, an on-line rapid detection method based on laser ranging sensor was proposed, a multi-parameter synchronous online detection system for combine screw conveyor was developed, and a detection test bench was designed. Through the structural relationship and sensor layout, the detection of the radial runout of the spindle, the radial runout of the spiral blade and the pitch of the screw were transformed into the detection of the corresponding distance information，which realized the continuous and synchronous measurement of multi-parameters. The experiment showed that compared with the traditional manual measurement method, which needed to select multiple measurement positions according to experience and took 15~20 minutes for a single measurement, the system can realize continuous and synchronous measurement of key parameters, and the single measurement time was 1 minute.The maximum relative error of spindle radial runout was 3.661%, the relative error of spiral blade radial runout was 2.030%, and the standard deviation of pitch measurement was 2.07mm, which met the detection requirements. Through the analysis and processing of the test data, the system realized the accurate positioning of machining error and 3D visualization display. According to the tolerance requirements, the screw conveyor was inspected and evaluated for compliance, and the over limit deformation was alarmed.