Abstract: As traffic flow increases and the demand for speed measurement accuracy rises, traditional radar speedometer calibration methods face numerous challenges in operational safety and data consistency. To address these issues, this paper proposes a standard speed measurement system based on the principle of three-laser ranging. The system employs a three-beam laser ranging array and utilizes Time-of-Flight (TOF) technology to accurately measure the vehicle’s instantaneous speed, while also being able to calculate the vehicle’s acceleration in real time. This allows the system to identify and exclude abnormal data, thereby significantly improving the stability and reliability of the speed measurement results. Through multiple comparative experiments, this paper systematically evaluates the performance of three-laser, dual-laser, and mobile radar speed measurement systems under different operating conditions. The experimental results show that the three-laser speed measurement system significantly outperforms traditional dual-laser systems and radar devices in terms of measurement accuracy, response speed, and data consistency, particularly exhibiting higher robustness in complex traffic environments. The three-laser speed measurement system not only provides higher precision and more stable measurement data but also effectively replaces the traditional “test vehicle method”, offering a safer and more efficient technical solution for the type evaluation and on-site calibration of radar speedometers. The research findings in this paper provide innovative ideas and technical paths for the precise calibration and standardized verification of traffic speed measurement technology, offering significant practical application value and advancing the high-quality development of speed measurement technology in intelligent transportation systems.