The invention discloses a correlation analyzing method based on vehicle, road conditions and safe travel big data in a network of vehicles. The method comprises the following steps of data acquiring, data transmitting and storing, data de-noising, data analyzing, and data display and feedback. The data acquiring process is not limited to data of the vehicles, and it also includes data related to roads and surrounding vehicles. With data classification and storage, removal of abnormal values through de-noising, as well as multivariate linear regression fitting analysis, the correlations can be determined and sent back to the owner of a vehicle among the conditions for dangerous driving, vehicle's hardware state, road environments, surrounding vehicles and driving behaviors. The analyzing method provided by the invention can enable drivers to learn about their driving behaviors and their vehicles' states. For the instant replacement of parts with potential to bring danger and the rectification of bad driving behaviors, the purposes can be achieved including energy reduction, vehicle lifetime extending, and safe driving.