Objectives To determine the relationship between marriage satisfaction and sexual functions in couples undergoing infertility treatment. Methods This cross-sectional study was conducted with 110 heterosexual couples who attended an outpatient infertility clinic in Turkey, between June 2018 and June 2019. Results In the study, 77.3% of the women and 43.6% of the men receiving infertility treatment experienced sexual dysfunction. Increased marital satisfaction is linked with better sexual function for infertile couples. Age, economic status, duration of marriage, type of marriage, duration of treatment, marriage satisfaction were determined to be significant predictive factors of the sexual functions of the infertile couples. Conclusion Healthcare providers may apply psychosocial care, education and counseling services toward increasing the marriage satisfaction and sexual functions of infertile couples.