Aiming at problems of the damping characteristics of a double-chamber hydro-pneumatic spring, the mathematical model of the damping force of a long circular hydro-pneumatic spring was established based on the Heygen–Blasius formula according to the practical drill way. By using the MATLAB Simulink simulation software, the influence of damping characteristics was researched by varying the structural parameters and exciting parameters. The results show that with exciting parameters increasing, the ergogram surrounding area of the spring system becomes large, and the curve of speed performance of the system is basically unchanged. The ergogram surrounding area decreases, and the curve of speed performance flattens with the increase of the area of the check valve damping hole. The ergogram surrounding area becomes smaller with the decrease of the area of the check valve, while the damping force and the curve of speed performance are not influenced in the stretching process. The hydraulic cavity area has basically no effect on the ergogram surrounding area or the curve of speed performance. With an increase in the ring cavity area, the ergogram surrounding area becomes larger and the curve of speed performance steepens.