Abstract: Group living brings numerous ecological benefits and costs, and changes in social status (such as from group living to social isolation) have a profound effect on the morphology, physiology, behaviour, and life history characteristics of social animals. Refuges are intricate and variable, however, most earlier studies on animal group behavior focused on a single ecological context. Therefore, to examine the effect of social isolation and ecological contexts on the group behaviour of cyprinid fish, we utilized common carp (Cyprinus carpio) as the experimental subjects, setting up two social status treatment groups (group-rearing, 5 fish maintained together; isolation group, single fish isolated alone). After 28 days, we measured the collective behavior of each treatment across three contexts: open water, food presence, and food+refuge. We found that, social isolation had no significant effect on the individual behaviour of common carp, but in the food context, both two groups had the fastest individual swimming speed, and in the food+refuge context, the synchronization of speed synchrony was the lowest. Social isolation and contexts have an impact on the collective behaviour and structure. The group speed and the percentage of time spent moving in group-rearing increased with context complexity. The isolation group exhibited a decrease in polarization and in both the open water and food+refuge displayed decreased group coordination and cohesion. After 28 days, foraging efficiency increased significantly in both treatments compared to day 0, while time spent in refuge decreased significantly. Group size in the isolation group was also significantly higher at day 28 than that at day 0. The study shows that social isolation reduces the activity and group coordination in common carp, and that increasingly complex ecological contexts improve the movement ability at the expense of group coordination.