<p>Mindfulness-based cognitive therapy (MBCT) has been demonstrated to be highly effective for improving sexual desire and reducing sex-related distress among women with sexual interest/arousal disorder (SIAD). The extent to which MBCT efficacy is impacted by relationship factors has not been studied to date and has implications for recommending MBCT to individual treatment seekers based upon their particular relationship characteristics. The goal of this study was to examine relationship status, relationship duration, self-reported relationship closeness, and relationship satisfaction as moderators of MBCT outcomes on sexual desire and sexual distress in 70 women with SIAD (Mean age 39.3&#xa0;years). Multilevel modeling examined the effects of these four moderators on outcomes at immediate posttreatment, and 6- and 12-month follow-up. Women who were single, those who self-reported not being emotionally close in their relationship, and those who had lower relationship satisfaction scores had significantly greater improvements in sexual desire after MBCT (<i>d</i> ranging from 0.49 to 0.99), and there was no effect of these relationship variables on sex-related distress. Years in relationship did not moderate either outcome. These preliminary findings suggest that single and relationally dissatisfied partnered women may benefit more from MBCT in terms of improvements to sexual desire compared to partnered and relationally satisfied women with SIAD.</p>