The purpose of this study was to investigate how a prosocial behavior psychoeducation program affected the problem behaviors and self-regulation abilities of preschoolers. In the study that employed the experimental research technique, a pretest-posttest control group was part of a quasi-experimental design. In the 2nd semester of the 2023-2024 academic year, there were 16 students in the experimental group and 18 in the control group, all of whom were preschoolers in the 5-6 age range. Data were gathered using the Problem Behavior subscale of the Preschool and Kindergarten Behavior Scale and the Self-Regulation Skills Scale for 4-6 Year-Old Children. It was determined that there was a significant difference in favor of positive ranks between the pre-test and posttest mean scores of the experimental group children regarding the inhibitory control-emotion subscale and self-regulation skills total. It was determined that there was a significant difference in favor of negative ranks between the pre-test and post-test mean scores of the experimental group children regarding the problem of expression, learning problems, and total values of problem behavior. Significant improvements were recorded in the variables considered in the experimental group after only nine weeks of training, demonstrating the effectiveness and feasibility of implementing age-appropriate programs in early childhood classrooms to improve children's social-emotional competence by enhancing their self-regulation skills and reducing problem behaviors.