Abstract: Addressing high-speed performance testing requirements for rail flaw detection equipment, a comprehensive rail flaw detection test simulation platform with maximum testing speed of 120 km · h^-1 was designed. By constructing a circular rail rotation system and flaw detection system, combined with multi-sensor safety monitoring and electrical control technologies, functions such as high-speed dynamic calibration of ultrasonic probe wheels and damage detection performance evaluation were achieved. Feasibility of the proposed design was verified through simulation analysis, dynamic balance analysis, motor selection, and key parameter calculations. Results demonstrated that this test platform could effectively simulate probe wheel high-speed detection states on rail surfaces, providing efficient and reliable testing means for rail flaw detection equipment development, upgrades, and performance verification.