In view of the special characteristics of metal materials in electrostatic field, a novel electrode capacitive sensor is designed to detect the flow velocity of metal particles in the pipeline. Firstly, based on the multi-electrode theory, a mathematical model for measuring metallic substance with capacitive sensor is formulated. On this basis, a 3D simulation model of the sensor is established by utilizing the COMSOL Multiphysics finite element analysis tool. The spatial sensitivity distribution characteristics of the sensor is analyzed. Then, based on the spatial filtering effect of the sensor, the principle of metal particle velocity measurement is introduced. The relationship between the cut-off frequency of the sensor output signal power spectrum and the metal particle velocity is established. Finally, a specific measurement system based on the triangular electrode capacitance sensor and the capacitance digital conversion chip Pcap01 is further developed. Experiments are verified and analyzed on a gravity transmission device. Theoretical and experimental results show that the measurement method has good repeatability. In the range of 2. 44 ~ 5. 34 m/ s, the repeatability error of the measurement velocity is less than 4% .