We propose a new approach to study the dynamical phase transition of RNAdS black holes on the underlying free energy landscape. By formulating a path integral framework, we can quantify the paths representing the history from the initial state to the end state of the phase transition. Then, the dynamics can be reflected completely. Based on these paths, we can calculate the kinetic rates and obtain the analytical expressions through the sums of the instantons. We find that the phase transition rate increases (decreases) with the temperate from the small (large) to large (small) black hole state transition. This is consistent with the change of the free energy landscape topography upon the temperature. Furthermore, the time evolution of the probability of starting from the small black hole initially and ending at the small (or large) black hole P (r s , t; r s , 0) (or P (r l , t; r s , 0)) is also given in this study.