Abstract: As the automatic vertical drilling tool equipped with a mechanical stable platform requires no electronic components and possesses good high-temperature resistance with low costs, it is a good choice for deviation prevention in deep well drilling. However,it has difficulty in further improving the deviation correction accuracy of the tool. Therefore, according to its dynamic characteristics, two mechanical stable platform models: a theoretical analytical one, and Adams dynamic simulation one were built on the basis of a typical stable platform structure and its working principle. Then, theoretical calculations and simulation calculations were conducted to study the factors affecting the performance of the stable platform, and the main influencing factors and laws governing the performance of the mechanical stable platform were determined. The research results revealed key performance influencers, which included the length, the inner and outer radius of the eccentric block, the inclination angle, and the dynamic friction coefficient between disc valves.Based on the results, the optimization direction and recommended value of the structural parameters of the mechanical stable platform were also summarized, and they can provide a reference for further design optimization for automatic vertical drilling tools with mechanical stable platforms.