Abstract: The measurement accuracy of measurement and control equipment is still one of the key issues in the field of measurement and control. The commonly used balloons, satellites, aircrafts and other calibration methods are difficult to coordinate, and the assessment cycle is often long, so it is impossible to achieve the purpose of test assessment with the real environment. The positioning accuracy of the global navigation satellite system (GNSS) has reached the order of decimeters or even centimeters, which can be used to assess the accuracy of measurement and control equipment. To make full use of the rocket-borne GNSS data obtained in the space launch mission, an accuracy assessment system for measurement and control equipment based on the rocketborne GNSS data was designed first, then the composition framework, working principle, key technologies and application scenarios of the system were introduced in detail. Finally, the arrow-borne GNSS data in the telemetry data of a measurement and control equipment was used to assess its measurement accuracy. The results show that the system realizes the accuracy assessment function in the measurement and control arc of the measurement and control equipment, which greatly enriches the traditional accuracy assessment method and has a good application prospect.