The current study aimed to improve the functional language of children with autism disorder, through a training program for applied behavior analysis, and the study sample consisted of (10) children with autism disorder, their ages ranged between (6-8) years with an average of (7.00) and a standard deviation (0.67), and the sample was divided into two experimental and control groups, each consisting of (5) children, and the study tools consisted of the Stanford-Interpersonal Intelligence Scale (fifth picture) (Tration: Mahmoud Abu Al-Nil et al., 2011), a scale of Gilliam Estimated Diagnosis of Symptoms and Severity of Autism Disorder, Third Edition "GAR-3" (prepared by Adel Abdullah Muhammad and Abeer Abul-Majd Muhammad, 2020), the functional language scale (prepared by: Adel Abdullah Muhammad, Abeer Muhammad Shehab), the training program for applied behavior analysis (prepared by: Adel Abdullah Muhammad, Abeer Muhammad Shehab), and the results revealed that there were statistically significant differences at (0.01) between the mean scores of the experimental and control groups in the functional language in the post-measurement in favor of the experimental group, and there were statistically significant differences at (0.05) between the mean ranks of degrees The experimental group in the functional language of measurement There are no statistically significant differences between the mean ranks of the experimental group's scores in the functional language in the post and follow-up measurements. Key words: Applied Behavior Analysis - Functional Language - Autism