Couple-based interventions (CBIs), despite strong efcacy in improving numerous HIV risk behaviors, are not widely available and have not been tested to improve women's antiretroviral therapy (ART) adherence. We examined barriers and facilitators to participation in a CBI based on cognitive behavioral couple therapy for women's ART adherence in KwaZulu-Natal, South Africa. Semi-structured interviews were conducted with women with HIV (n=15) and men of mixed HIV status (n=15). Thematic analyses were guided by the Consolidated Framework for Implementation Research. Facilitators mostly related to the couple's relationship, including having an existing healthy relationship, men's desire to support their partners, and a potential opportunity for men's HIV disclosure. Barriers included a lack of understanding of how a CBI approach would be useful for women's ART adherence, sole focus on women if male partners were also living with HIV, and men's lack of prior HIV status disclosure to female partners. Findings indicate that relationship context and the male partner's HIV status need to be addressed during recruitment, enrolment, and during the intervention to promote uptake.