Sexual desire disorder is the most common form of sexual dysfunction among women and is associated with problems like sexual distress and reduced sexual self-disclosure. As a result, this RCT study was conducted with 70 reproductive-age women in the form of 4 weekly group educational sessions. Compared to the control group, the mindfulness-based cognitive-behavioral sex therapy (MBCST) intervention significantly improved sexual -desire, -distress, self-disclosure and -function immediately, 4 and 12 weeks after the educational sessions were completed in the intervention group (p < 0.001). Overall, our findings underscore the significance of the MBCST intervention on improving sexual dysfunction among women.Trial registration number: Iranian registry of clinical trials. IRCT Id: IRCT20160808029255N4.Trial registration date: 17th September 2018.Date of first patient's enrollment: 19th September 2018.Supplemental data for this article is available online at https://doi.org/10.1080/0092623X.2021.2008075.