Expressway traffic accident alarm device and alarm method

The invention discloses highway traffic accident alarm equipment and an alarm method, and relates to the technical field of traffic alarms, the highway traffic accident alarm equipment comprises a working frame of a rectangular structure and a blocking and warning mechanism, and the blocking and warning mechanism comprises a mounting underframe, a telescopic mounting rod and a movable plate. When the highway is monitored, the working frame is driven by the moving mechanism to move on the side of the highway, the monitoring and alarming mechanism can be started for further monitoring, judging and alarming when the speed of the road surface becomes slow and congestion occurs, and four different colors of laser are generated through the monitoring and alarming mechanism, so that the highway is monitored. Different colors correspond to different lanes, when the laser irradiates the lanes, a driver behind can judge the lanes where traffic accidents happen through the different colors, and due to the fact that the