As a psychological intervention, art therapy uses the creative, symbolic, and sensory capacities of art to modulate emotion, increase self-awareness, and improve psychological adjustment. The theoretical basis of this approach is based on the assumption that emotional experience is not processed solely through verbal language, and that an important part of emotions, memories, and internal conflicts can be manifested and organized in the form of images, colors, forms, movement, and the creative process. Emotional system regulation refers to the set of processes through which a person manages the intensity, duration, direction, and expression of his emotions. In this framework, art therapy can act as a safe space for experiencing, observing, and reprocessing emotions and creating a constructive distance between the individual and the emotional experience. The process of creating a work of art shifts the individual's attention from immediate emotional reaction to active observation and processing of the experience and can provide the ground for increasing emotional flexibility. One of the important mechanisms of this intervention is emotion externalization, which means that the internal experience is removed from a vague and purely subjective state and organized into a visible work. This process can help identify emotion, name it, and understand the relationship between thoughts, feelings, and behavior. From a cognitive perspective, artistic activity provides the possibility of re-enacting the experience and creating a cognitive distance from negative thoughts. Instead of being overwhelmed by emotion, a person can observe, change, and reinterpret it. From an emotional perspective, artistic activities can help reduce arousal, increase the sense of control, and enhance the experience of self-efficacy. Research in the field of art therapy has shown that art interventions in some clinical groups have been associated with a reduction in psychological distress, anxiety, depressive symptoms, and an improvement in quality of life. Research evidence also emphasizes the role of art activities in facilitating emotional expression, increasing self-awareness, and strengthening coping strategies, although the intensity and persistence of these effects are not the same in different studies. In some studies, art therapy has shown a significant communicative capacity, especially for people who find it difficult to verbally express emotions. Painting, drawing, collage, music, drama, and other creative activities can be selected according to the individual's characteristics and the goal of the treatment. The application of art therapy in regulating the emotional system is not limited to reducing negative emotions, but can also help to reinforce positive emotions, increase the sense of meaning, promote resilience, and develop self-regulation skills. In the therapeutic process, the therapist can use a guided dialogue to explore the feelings, thoughts, memories, and meanings associated with it, after creating the work. Therefore, the artwork is not considered the ultimate goal of the intervention, but can be used as a medium for the recognition and processing of the psychological experience. Another important application of this approach is to help regulate emotion in stressful situations and traumatic experiences, as creative activity can allow for the indirect and gradual expression of difficult experiences. In clinical settings, art therapy can be used alongside standard psychotherapies to manage anxiety, depression, stress, and adjustment problems. In psycho-oncology, the purposeful use of art can help cancer patients express fear, anger, sadness, worry, and experience physical changes, providing an opportunity to reconstruct the meaning of the disease. However, the important challenge is that art therapy should not be reduced to merely a fun activity or the production of an aesthetic effect, but should be implemented based on specific therapeutic goals and professional principles. The interpretation of artistic symbols should also be done with caution, as an image or color does not mean the same for everyone, and attributing fixed meanings to artistic elements can lead to incorrect perceptions. Limitations include differences in intervention protocols, limited sample sizes, heterogeneity of study groups, differences in measurement tools, and difficulty in separating the effect of art therapy from associated factors. Also, the quality of therapist training and the degree of adherence to professional frameworks can affect the results of the intervention. It is suggested that future studies with larger samples, controlled designs, long-term follow-ups, and validated tools for measuring emotion regulation be further investigated, and the precise psychological and neuropsychological mechanisms of art interventions should be further investigated. It is also necessary to design standardized yet flexible protocols appropriate to the age, culture, clinical status, and individual needs of clients. The use of art therapy along with approaches such as cognitive-behavioral therapy, mindfulness, and acceptance and commitment therapy can also increase the capacity of multidimensional interventions for emotion regulation. Overall, art therapy can be considered as a complementary and process-oriented approach that has a potential to support the regulation of the emotional system through externalizing emotion, increasing self-awareness, cognitive distancing, experience of control, and reconstructing meaning, however, its effectiveness should be evaluated based on empirical evidence, individual characteristics, and specialized and ethical implementation.