Introduction: Infertility is defined as failure to conceive a pregnancy despite a year or more of regular sexual activity without contraception55. Infertility is divided into primary and secondary, and its etiologies include male, female, male and female causes, as well as unexplained. Therefore, the present study aimed to determine the types and causes of infertility in couples referring to an infertility treatment center in Bojnurd during 2018-2023. Method: This cross-sectional study was conducted using a checklist made by the researcher on all couples who were referred to the infertility clinic in the Bent-Alhoda Hospital, Bojnurd, in North Khorasan, from 2018 to 2023. The information was extracted from the files or contact with the patients in cases of non-registration. Thereafter, data were entered into the SPSS statistical software (version 25). Following that, analysis was performed using descriptive indicators, frequency distribution, and analytical statistical tests, namely Chi-Square, independent t-test, and one-way analysis of variance, at a confidence level of 95%. Results: The mean age scores of women and men were 30.04±6.65 and 34.28±7.14 years, respectively. The mean body mass index of women was 26.10±4.87 Kg/m2. Moreover, 87.3% of women were unemployed, and most men were freelancers. The majority of women (76%) had no underlying disease. The most common types and etiology of infertility were related to primary infertility (55.9%) and unexplained causes (38.5%), retrospectively. Conclusion: Training classes to inform couples about the controllable risk factors of infertility is an essential step towards reducing the incidence of these factors.