<p>Women’s attitudes toward menopause (ATM) can greatly affect their quality of life. There is substantial evidence that educational interventions positively influence the self-care in menopausal women and perhaps their ATM. Digital technologies, such as smartphone apps, may offer a way to facilitate and improve access to self-care education during menopause, which expected to improve women’s ATM. The present study sought to investigate the effect of a mobile app-based self-care training program on postmenopausal women’s ATM in Iran. This clinical trial was conducted in 2021 among 60 postmenopausal women selected through convenience sampling and randomly allocated into intervention (<i>n</i> = 30) and control (<i>n</i> = 30) groups via a lottery method. While the control group received only routine care, participants in the intervention group utilized a menopause self-care application for eight weeks in addition to routine care. The participants in the control and intervention groups completed the ATM Scale before and after 8 weeks. The data were analyzed using SPSS-16 software, with descriptive statistics (mean and standard deviation) and inferential statistics (t-test, ANOVA, chi-square, Pearson’s correlation, and ANCOVA). The ANCOVA results showed that compared to the control group, the intervention group had significantly higher post-test scores for women’s ATM (r² = 0.863, <i>P</i> = 0.01). The data from this study confirmed a strong, positive effect of a mobile app-based self-care training program on postmenopausal women’s ATM. We recommended using a mobile app for menopause women’s self-care training as a cost-benefit and accessible method.</p><p><i>Clinical trial number</i>: The protocol for the present study was registered under number IRCT20201226049833N1 in the IRCT.</p>