To understand the characteristics of a driver who frequently change lanes and analysing the mechanisms of frequent lane-changing behaviour. The authors collected data via video recording and questionnaire and analysed the influence of traffic environment and driver characteristics on frequent lane-changing behaviour by mathematical statistics. Results showed that the traffic environment of three lanes, small cars and traffic flow density were strongly correlated with frequent lane-changing behaviour. The drivers were the main factors affecting frequent lane-changing behaviour, which was most prevalent during aggressive driving. Only 26.4% of drivers never engaged in this behaviour. Most prone to frequent lane-changing behaviour were males, 31-40 years old and with low academic qualifications and choleric personalities. These findings have a significant role in realising dynamic assistance and providing a security warning to the driver. Obtained baseline data could be used for driving-behaviour recognition and guidance for the improvement of road condition. Furthermore, results could enrich the traffic data related to lane-changing behaviour and provide theoretical support for the development of vehicle infrastructure cooperative system and automatic driving, which will contribute to building future sustainably intelligent mobility.