Background: Abundant high-risk behaviors in trans-sexual people make it necessary to investigate. Objectives: This study aimed to describe and determine high-risk sexual behaviors. Materials and Methods: This study was cross-sectional. Ninety-six sex-reassigned transsexual individuals of both genders presenting to Salamat Bonyan Psychology Clinic were enrolled in the study. The sampling method was through the census. Eligible individuals were recruited using convenience sampling. The scales included a demographic characteristic form and a researcher-made questionnaire to evaluate high-risk behaviors and sexual health of sex-reassigned transsexual subjects. Descriptive statistics, including frequency distribution and also mean and standard deviation (SD), were used to describe. The SPSS software version 16 was used for data analysis. Results: According to the results, 96 individuals completed hormone therapy, of whom 43 underwent sex-reassignment surgery. Also, 73 persons were female-to-male, and 23 persons were male-to-female. (62.5% CI: (0.52 - 0.72)) of the participants did not receive hepatitis B, and (95.83% CI: (0.92 - 0.99)) human papillomavirus vaccination. (87.09% CI: (0.68 - 0.85)) of the participants did not take an human infection virus (HIV) test and (97.9% CI: (0.95 - 0.99)) a Pap test. (99% CI: (0.89 - 0.99)) of the participants were never screened for prostate cancer, and (91.66% CI: (0.86 - 0.97)) for breast cancer. Oral sex was the most common sexual act way (93.75%), and (72.91% CI: (0.68 - 0.77)) never used condoms. (30% CI: (0.20 - 0.39)) of the participants smoked hookah and cigarettes and used alcohol. Conclusions: Considering high-risk behaviors and sexually risky behaviors in this group, it is necessary to carry out preventive interventions.