Many studies will emphasize the importance of family systems for drug addicts and constantly mention in various brochures and publications all the time. We know the risk factors how to impact people addiction by evidence-based studies, but the protective factors is not. In this paper, we try to describe the protective factors of the family system in the prevention, treatment and recovery, have different essentials to work with drug abusers. On the other hand, we also summarize the studies of family structure and family needs, family relationship and family communication, family function and family support, and hope to explain the intangible means and to examine family as an influential factor for adult drug abusers. A case report is presented to reflect upon the intertwined relationships between family system and protective factors. The theory of career construction is applied to examine our case. Hopefully, the case study can help us gain a better understanding of family as the protective factors, and identify different meanings for individuals, more than before.