Mars rover is an essential carrier to perform complex exploration missions on the Martian surface. To ensure the reliability of the rover， the principle of the Mars rover dynamics is studied. Firstly， we analyze the structure and composition of the rover and introduce the basic theory of the rover dynamics modeling. Then， based on the Lagrange recursive dynamics analytical method， the Lagrange equations of the multi-axis system are obtained， in which the axis-chain system of the rover’s directed Span-tree is introduced as a reference. The dynamics model of the Mars rover is established by traversing the topology of its axis-chain. Subsequently， the symbol system of chain-ordering is introduced into the classic Bekker’s terramechanics model to improve its accuracy. Finally， dynamics simulation software is built in the MFC framework of the VS platform， where the dynamics system is tested to verify the accuracy and real-time performance of the dynamics modeling and control of the rover.