Abstract: To effectively detect and treat rail corrugation disease, a dual-track rail corrugation detector based on laser triangulation ranging method is designed. The corrugation detector overall structure, the detection system hardware composition and the core software system functionality are introduced. By adopting chord measurement principle and dynamic reference chord structure, the corrugation detector can realize non-contact dynamic measurement of corrugation on the top surface of both tracks simultaneously, and has functions of recording, playback and analysis of measurement data throughout the entire process. By comparing and analyzing the detection data of the corrugation detector and RMF1100 corrugation trolley, the repeatability and authenticity of the corrugation detector detection data and detection reliability are verified. The field trial in Kunming Metro shows that using this corrugation detector can greatly improve detection efficiency and achieve accurate measurement of rail corrugation, providing an efficient and reasonable solution for the detection and treatment of rail corrugation disease.