Marital adjustment is an evolutionary process between a husband and wife that is created, strengthened or weakened in life. Mental health and healthy and pleasant sexual functioning seem to be important in promoting it. The aim of this study was to determine any correlations of marital adaptation with stress, anxiety, depression or sexual function and its components. This cross-sectional study was done on 514 women of reproductive age who were referred to health centers in Shiraz and were chosen by random sampling. The Spinner marital adaptation questionnaire, the Female Sexual Function Index (FSFI) and the Depression, Anxiety and Stress Scale (Dass-21) were the study tools. The statistical tests applied for data analysis were the t-test, Fisher’s, chi-squared and Pearson’s coefficient correlation. Marital conflict was reported in 54.7% of women. The average score of sexual function was significantly less in maladaptive patients than in adaptive ones (22.32 ± 7.05 versus 26.53 ± 5.01). There was a significant link between marital adaption and components of sexual function (p < 0.05). The mean scores of stress, anxiety and depression in the maladaptive group were 9.14 ± 4.74, 6.60 ± 4.56 and 7.75 ± 4.79 versus 6.53 ± 4.62, 4.48 ± 3.93 and 4.06 ± 4.21, respectively, which was statistically significant (p < 0.05). As to data analysis, sexual function, stress, anxiety and depression affect marital adaptation. Therefore, providing the necessary relevant education can improve the family health, couples intimacy and marital satisfaction.