The current study aimed to verify the effectiveness of a group counseling program based on acceptance and commitment therapy (ACT) in reducing the level of nomophobia among ninth-grade female students in Muscat Governorate. To reach the objectives of the study, the interactive electronic nomophobia scale and the group counseling program based on acceptance and commitment therapy were used. The program consisted of twelve counseling sessions. The study followed the experimental approach with control and experimental groups, with pre- and post-test and a followup test. The study sample consisted of 30 female students, distributed equally into two control and experimental groups. The results of the study indicated that there were statistically significant differences between the averages of the pre- and post-test of the experimental group on the nomophobia scale in favor of the post-test. There were also statistically significant differences between the averages of the post-test of the experimental and control groups on the nomophobia scale in favor of the experimental group. The results also showed the continued effectiveness of the group counseling program. The treatment based on acceptance and commitment reduced the level of nomophobia among female students in the experimental group, and the positive effect of the program remained even a month after its completion.