BACKGROUND: Today, one of the biggest concerns of parents is protecting their children and properly educating them about sex. The aim of this study was to determine the effect of educational intervention on parental skills in sex education on their children in elementary schools in the northwest of Tehran-Iran in 2019 based on literature. MATERIALS AND METHODS: This quasi-experimental study was conducted on 125 parents of elementary schoolchildren in the northwestern of Tehran. The data were collected by valid and reliable questionnaire. Before the intervention, two intervention and control groups filled up the pretest questionnaire; the data were collected by valid and reliable questionnaire. Before the intervention, two intervention and control groups filled the pretest questionnaire, and then the parents participated in the educational program based on dramatic literature. Two months later, the same questionnaire was completed by the control and intervention groups. Finally, the data were analyzed by regression and one-way ANOVA test. RESULTS: The results showed that there was a statistically significant difference between the mean scores of knowledge in the experimental and control groups in the posttest (P < 0.01). There was also a statistically significant difference between the mean scores of attitude in the experimental and control groups at the posttest stage (P < 0.01). There was also a statistically significant difference between the mean scores of performance based on group membership (experimental group and control group) in the posttest phase (P < 0.01). CONCLUSIONS: The findings of the study showed that educational intervention on parental skills in sex education based on the dramatic literature to their children has significant effect on parental knowledge, attitude, and performance.