The main objective of this article is to find the greatest method for collecting the data for VANET in terms of communication overhead, average latency and packet delivery ratio. This article is used to identify the various levels of techniques for data collection in VANET at single RSU. A VANET is composed of fast-moving mobile nodes (vehicles) that have irregular and short contacts, fixed road-side units (RSUs) that overhear and broadcast to vehicles, and a central server. Vehicles move along roads, collect data and process them, and distribute the data to other vehicles and RSUs. The central server aggregates data collected by vehicles, overviews traffic and road status, and generates keys and certificates when necessary. RSUs overhear the data sent from vehicles, broadcast road-side information to vehicles, and communicate to the central server via backhaul network. Date collected from the different resources is organized using different levels of data. We have presented data mining techniques for mining the data in VANET.