Over the past decade, studies have demonstrated that a shift in attentional patterns from goal-oriented top-down attention to bottom-up attention to external stimuli under acute stress involve reallocating resources between different neurocognitive networks,which is a heterogeneous process. However, it remains unclear that how this neural functional coupling regulates the activation and termination of hypothalamic-pituitary-adrenal (HPA) axis, the major endocrine stress system. To bridge this konwledge gap, seventy-seven participants (age, 17–22 years, 37 women) were recruited for a ScanSTRESS brain imaging study, and their salivary cortisol levels during stress were collected. In addition, we assessed individual differences in the sensitivity of behavioral activation system (BAS) and funtional connectivity of the brain in all participants. We found that functional couplings among the dorsal attention network (DAN), central executive network (CEN) and visual network (VN) decreased significantly during repeated stress induction. The decline of functional connectivity could single a rapid cortisol recovery and the level of BAS could moderate the relationship between neural changes and cortisol reactivity and recovery. In all, this study suggested the important role of functional connectivity between CEN and DAN in the process of stress resilience, and the promotive effects of reward sensitivity measured by behavioral activation system.