Background: There is some evidence about alteration of sex hormones in patients with COVID-19 infection. This study aimed to evaluate the levels of sex hormones in female and male patients with COVID-19 during hospitalization and one month after discharge. Methods: The levels of sex hormones including estradiol, progesterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone, and free testosterone were measured in 162 female and male patients with COVID-19 infection during hospitalization and one month after discharge. A demographic questionnaire and a checklist were used to collect the data. The ANCOVA test was used to compare the level of hormones in patients with severe and moderate disease. Results: In the primary assessment, 162 patients were assessed for serum levels of sex hormones, while a month after discharge, only 69 patients provided consent for assessment, and nine had passed away. During hospitalization, female patients with severe disease had an elevated level of estradiol (407.70±623.37 pg/mL) in comparison to those with a moderate disease (213.78±407.17 pg/mL). The levels of progesterone and LH were high during hospitalization, but there was a decrease in these levels after discharge. The reduction in the level of FSH in patients with severe disease was greater than in patients with moderate disease, which increased after discharge. While the level of testosterone decreased during hospitalization, the alteration of free testosterone was negligible in male patients.Conclusion: In this study, we observed alteration in sex hormones (increased level of estrogen, progesterone, LH and reduction in the level of FSH and total testosterone) in female and male patients, with the alteration being greater in the latter. Due to the attrition of patients in follow-up period, more studies are needed to confirm these results.