The purpose of this study was to explore practical strategies that social workers used in student guidance in secondary school. In-depth interviews were conducted to collect data from 12 school social workers. Two types of strategies were found: Direct strategies (education, intervention, and mediation) and indirect strategies (consultation, cooperation, and advocacy). And two targets of treatment were found: the individuals and their ecological systems (family, school, and community). Thus, school social workers provided professional service with both individual and ecological targets, and also used several strategies which were different from counseling and education. Lastly, several suggestions were recommended for future practice: (1) division and cooperation of multi-professional practitioners; (2) working from an ecological system perspective with multi-strategies.