Self-injury behavior is a behavior that can cause or potentially cause redness, bruising, or injuries to body parts. Some of the children who perform such behavior are children with Autism Spectrum Disorder (ASD). Children with ASD perform self-injury to seek attention, avoid things they dislike, to obtain what they want, or for self-stimulation. In this study, the children who were participants in the study were 10-year-old boys who had ASD conditions with below-average intelligence problems and carried out self-injury behaviors in the form of hitting the chest using their hands. The hitting-chest behavior carried out by the participants had been excessive, causing redness in part of each child's chest, pain in the chest, and sometimes a feeling of breathless. Therefore, a study was performed to eliminate the behavior of hitting the chest by applying intervention using the method of shaping and differential reinforcement of alternative behavior (DRA) according to the principle of behavior modification in children with ASD. The given alternative behavior is a stroking-chest behavior. After administering the intervention for 18 days (2 days of shaping session and 16 days of DRA sessions), the researchers obtained the results that the shaping and DRA methods are effective to eliminate the hitting-chest behavior and shape the stroking-chest behavior as an alternative behavior in children with ASD whose intelligence is below the average.