BACKGROUND: Sexuality plays a critical role in a woman's postpartum quality of life and also has a strong impact on the quality of her relationship. Given the sparse body of published literature on the subject, we aimed to explore how new mothers explain their postpartum sexual quality of life. METHOD: A qualitative study was carried out in Iran and Switzerland from December 2018 to March 2019. Focus groups and semi-structured in-depth interviews (IDIs) were conducted with mothers in the first four months after parturition. Mothers who were older than 18 years, were married or in a stable relationship, and experienced a low-risk vaginal birth or cesarean section participated in the study. We used Graneheim and Lundman's approach for analyzing the data. Multiple data collection methods, maximum variation sampling, and peer checks were applied to enhance the rigor of the data. RESULTS: We achieved data saturation after two focus group discussions (FGDs), 15 IDIs in Iran, and 13 IDIs in Switzerland. We extracted three themes for postpartum sexual quality of life: (a) sexual worldview, (b) interpersonal relationship, and (c) postpartum sex storm. The participants described sexual worldview as "sexual beliefs", "sexual perceptions", and "sexual behaviors". The interpersonal relationship consists of "changes in postpartum interpersonal relationships" and "supportive role of the husbands/partners". The last one, postpartum sex storm, has three categories including "direct changes in sexual life", "indirect changes in sexual life", and "resumption of sexual intercourse". Differences between the two cultures were identified in some subcategories such as "sexual interests", "comparable to the first intercourse in life", "negative sexual behaviors of husbands/partners", "positive sexual behavior of mothers", "helping with child care and housework", and "emotional support". CONCLUSION: New mothers explained postpartum sexual quality of life as a three-theme phenomenon. Although most results were similar in both cultures, there were some differences. Our study's results suggest that sexual quality of life is a topic that encompasses international as well as cultural aspects.