This research followed a qualitative design to identify preschool teachers’ mindsets about workload-related stress. Twenty in-service Chinese preschool teachers were invited to delineate their perceived workload-related stress consequences. Directed by a hybrid of inductive and conductive approaches, we conducted thematic content analyses on two rounds of in-depth teacher interviews. Findings suggested that workload-related stress was like a two-edged sword for preschool teachers. On the one hand, teachers regard workload-related stress as enhancing in the aspects of motivating them to shift working strategies, to refine professional learning, to issue teacher leadership, and to mobilize colleague teachers’ teamwork. On the other hand, some teachers’ mindsets focus on the downsides of their workload-related stress, emphasizing its deleterious influences on working efficiencies, emotional wellbeing, as well as its spillover effects on family life. Teachers’ individual-, preschool- and sociocultural-level elements were discussed to explain the patterns of Chinese preschool teachers’ workload-related stress mindset.