In recent years, with the continuous development of sensing technology, using inertial sensor network to obtain the posture of equestrian athletes can effectively improve the information analysis and technical guidance ability of equestrian athletes. This paper intends to study an evaluation model of equestrian athletes’ speed sense based on inertial sensor network. In this paper, MPU6050 (MPU stands for Motion Processing Unit in MPU6050) six-way inertial sensor is selected as the sensor module of the athlete speed acquisition system. Its main advantage is that the three-axis accelerometer and the three-axis gyro are integrated together, which not only solves the inter-axis difference between them, but also greatly reduces the packaging space, and realizes the minimum packaging size of wearable electronic products, thus achieving the optimal position and posture acquisition and monitoring. When the time is 0.000000001s, the speed of the horse is 35.4km/h and the posture angle of the athlete is 35.23. This paper is helpful to evaluate the speed sense of equestrian athletes and improve the equestrian training level.