Abstract: In order to realize the velocity measurement of moving solid-surface, a novel spatial filtering velocimeter based on linear image sensor was established and a new method was proposed to ensure the error source of the system. The image sensor was employed both as a detector and as a pair of differential spatial filters so that the system was simplified. The spatial filtering characteristics of the linear image sensor were investigated theoretically and the driving circuit and the signal acquiring and preprocessing circuit were designed. The velocity of a conveyor belt using a high-precision turn table as the driving wheel and the radiating frequency of a lamp were measured. The experimental results show that the measurement error of velocity of conveyor belt was within 0.77% and the measurement uncertainty within 11 minutes was 0.66%; the radiating frequency of a lamp was measured under the condition of no imaging system, and the measurement uncertainty turned out to be 0.056%, which was an order better. In a word, the velocimeter can satisfy the requirements of non -contact, real -time, high precision and high stability velocity measurement of a conveyor belt.