Play therapy is an effective psychotherapeutic tool for children, supporting their emotional and social development. During the therapeutic process, the psychologist accompanies the child in play, enabling the expression of thoughts and feelings that might otherwise remain unspoken. Play creates a safe space for developing social skills, regulating emotions, and building a therapeutic relationship, while also serving preventive and intervention functions in cases of emotional and behavioral difficulties. The aim of this paper is to analyze play therapy as an effective method of supporting children’s mental health. The study is based on a review of recent scientific literature available in the PubMed, Medline, and Heal-Link databases, including publications in English. The results of the analysis indicate that play therapy is particularly effective for preschool and early school-aged children, especially those experiencing stress, grief, domestic violence, and neurodevelopmental disorders. This method promotes the development of social competencies, supports emotional and behavioral regulation, and contributes to the reduction of negative emotional states. Empirical studies confirm its positive impact on children’s overall psychosocial functioning. In conclusion, play therapy is a well-established and effective form of psychological support for children. It enables the safe processing of difficult experiences within a symbolic space and supports emotional and social development, contributing to improved mental health and overall functioning.