Stepped into the network information age, the network collective actions increase rapidly which make them the new focuses of researchers. Based on the social exchange theory, ERI (Effort-Reword Imbalance) model explores the balance between effort and reward in formation mechanism and action mechanism of social stress. From this perspective, we analyzed the dynamic mechanism of network group collective action events. We believe that the emergence of network collective action events relates to the participants’ pursuit for social justice. The feeling of injustice caused by the imbalance between the effort and the reward of participants is an important driving factor of these events. On this basis, some strategies are proposed, hoping to give an integrated thought to public administration department in coping network collective action.