The invention discloses a passenger waiting time application model based on departure intervals of buses and a model establishing method. Bus stations are classified based on whether the bus stations are directly connected with a rail transit system or not, different passenger arrival probability density distribution functions are established, the relations between the different functions and the departure intervals of the buses are acquired respectively, a first passenger waiting time sub application model and a second passenger waiting time sub application model are established according to the relations respectively, and then the passenger waiting time application model is established. The passenger arrival rate distribution functions of the bus stations directly or indirectly connected with rail transit are determined, and an optimal fit application model is found; the relation between arrival rate distribution and the departure intervals is determined, the passenger waiting time application model corresponding to different types of bus stations is determined, and therefore the average passenger waiting time is accurately calculated, improvement measures are proposed for the analysis service level of a bus system to point out the direction, and huge application potential is achieved.