With the rapid development of regional integration, the adjacent city mobility is becoming increasingly active, adjacent city masses have new requirements to set the public transport operation passenger line of the adjacent city. To grasp the passenger transport demand of the passenger transportation route in the adjacent city is an important prerequisite for the study of the adjacent city passenger transportation. Based on the analysis of passenger flow characteristics and influencing factors, the paper analyses the models and methods for forecasting passenger demand, according to the characteristics of passenger flow, a method to predict the trend of passenger flow and passenger flow in the public transport operation passenger line of the adjacent city is determined. It has important reference value for the construction of the adjacent city transport network, transport capacity and transportation policy.