Demand response transit ( DＲT) serves is a new type of public transportation service mode． In order to make DＲT theory more suitable for practical application in low-density population areas，a flexible bus scheduling model considering multiple vehicle types and multiple operating modes was proposed． First，dual decision variables for vehicle type and route were set up，and then a flexible bus dispatch model that considers multiple vehicle types as well as multiple operating modes was built． Then，a hybrid genetic ant colony algorithm HGACO，which is composed of nearest neighbor search algorithm，2-opt method，destination dimensionality reduction operator，genetic algorithm and ant colony algorithm，was designed using the hybrid model of“large loop and small loop”． Finally， taking the three sections from the southwest part of the city to the city center as an example for scheduling，the results show that the flexible bus dispatch model considering the multi-vehicle and multi-ple operation mode is practical and operable，and it can make DＲT in low-density areas more scientific and economical． The improved hybrid algorithm HGACO is superior to the original algorithm in solution ability，accuracy and stability，and can stably obtain a better solution to the DＲT flexible scheduling problem．