Abstract: To examine the effects of aqueous extract of Albizia julibrissin Durazz bark on growth performance, active behavior, and anxiety-like behaviour in fish, juvenile common carp (Cyprinus carpio) were continuously fed for 25 days with artificial diet soaked in the aqueous extract (treatment group), while the control group received untreated artificial diet. Body weight and length were measured on day 0 and day 25. An open field test was used to assess activity (total distance moved and swimming speed) and anxiety-like behaviour (freezing time, time spent in the central zone, number of entries to the central zone, and latency to the central zone). The results showed no significant differences in specific growth rate (SGR), feeding efficiency (FE), or feeding rate (FI) between the two groups. After 25 days, freezing time was significantly higher in the treatment group compared to the control group, and freezing time increased from day 0 to day 25 in both groups. Albizia treatment had no significant effect on other anxiety-like behaviour parameters such as time spent in the central zone or latency to the central zone. Regarding activity, Albizia treatment did not alter total distance moved or swimming speed; however, speed significantly decreased in both groups after 25 days of acclimation. This study indicates that 25 days of feeding with diet soaked in Albizia julibrissin aqueous extract does not affect growth, feed utilization, or activity level in common carp, but it increases freezing time, suggesting that Albizia julibrissin may enhance vigilance or risk assessment tendencies in fish. However, whether it belongs to a typical anti-anxiety effect still needs to be distinguished and verified by combining multiple dose gradients, positive controls, and neuroendocrine indicators.