In order to deeply explore the nature of universal gravitation, on the basis of classical Newton's theory of universal gravitation, combined with the theory of relativistic dynamics and the equivalence principle, Newton's theory of universal gravitation is appropriately extended, and a modified Newton's gravitational equation is proposed. The planetary motion orbit equation and perihelion shift are derived by using the modified Newton's theory of universal gravitation. With the precession of Mercury's perihelion as an example, the rationality of the modified Newton's theory of unversal gravitation is verified.

%U https://zkxb.jsu.edu.cn/EN/10.13438/j.cnki.jdzk.2020.04.009