The invention relates to a device for measuring the motion state of any mass point of a cylindrical helical spring under an impact load. The device comprises a left inner tube and a right inner tube which are arranged at the two ends of a transition frame, wherein the other end of the left inner tube and the other end of the right inner tube are arranged on a left end cover and a right end cover respectively; a large mass block is arranged in the right inner tube; a small mass block in clearance fit with the large mass block is arranged in the large mass block; the transition frame is provided with a through hole through which the small mass block passes; the wall of the through hole is provided with a step for limiting the large mass block; and a sensor for detecting that mass points pass through the spring is arranged outside a left outer tube and is connected with a data analysis unit. The device can determine the displacement, speed and acceleration of any mass point at any time so as to quickly and effectively detect the performance parameters of the spring and facilitate improving the design and manufacturing quality of the spring, quickly and accurately measures the motion state, has a short period and low equipment cost, is easy to realize, can simulate different impact working conditions of the cylindrical helical spring in practical application, is flexible in use and has a wide application range.