Research has underscored the significance of social-emotional learning (SEL) on children’s academic achievement and cognitive development. Yet, there remains a significant gap concerning the influence of SEL programs on preschool children’s mental health and learning motivation. Understanding young children’s attitudes and engagement towards SEL programs can help us know how they perceive social relationships and build social and emotional development at a young age. Therefore, this study aims to use a mixed method approach to examine the efficacy of SEL programs in promoting their mental health, and to measure children’s feelings and willingness to participate in SEL activities and their attitudes toward SEL-related scenarios. Quantitative findings revealed that preschool children are more likely to participate in SEL activities, while qualitative results found three main themes about their attitudes, indicating a positive reception of SEL, and suggested a lasting improvement in preschooler’s mental health and social relationships. Implications are provided as follows.