The invention discloses a method and a system for analyzing the first-time city entering behavior of a vehicle. The method comprises the steps of acquiring vehicle passing data, and generating a vehicle passing record table and a vehicle city-entering index table according to the vehicle passing data; segmenting the generation time range of a case into a plurality of time periods by adopting a time segmentation function, and transmitting the time periods to an original recording thread pool; calling the original recording thread pool to inquire a vehicle passing record list; according to the plurality of time periods, inquiring the vehicle passing record table in the starting and ending time corresponding to each time period; summarizing all inquiry results to obtain a suspected vehicle data set; segmenting the suspected vehicle data set into a plurality of data segments and transmitting the data segments into a backtracking check thread pool by adopting a record segmentation function;calling the backtracking check thread pool to inquire the vehicle city-entering index table through multiple threads; if the suspected vehicle information is not recorded in the vehicle city-enteringindex table, determining that a vehicle corresponding to the suspected vehicle information is driving into a city for the first time within the generation time range of the case; and merging all processing results to obtain a first-time city entering data set. According to the method and the system, vehicles, driving into the city for the first time, can be efficiently inquired.