Vehicle platooning, a beneficial feature of automated driving environments, is likely to affect the lane change behaviour of manually driven vehicles (MVs) because identifying proper gaps in vehicle platoons in the target lane will be more difficult than in the current non‐platooning environment. These interactions between MVs and automated vehicles (AVs) could lead to a higher potential for unstable traffic flow, which is closely associated with traffic safety issues. The objective of this study was to investigate the lane change characteristics of MVs in AV platooning environments using driving simulator experiments. This research found that MV drivers tend to show more radical driving behaviour, as indicated by greater steering magnitude and steering velocity when they change lanes into the platooning vehicles’ lane. Therefore, novel traffic operations strategies to manage MVs and AVs effectively are required to ensure traffic safety, which will be conducted by a future study.