Male infertility in β-thalassemia patients is typically considered to be the consequence of iron deposition in the endocrine glands. Adult male patients with β-thalassemia, on regular blood transfusions, are prone to developing acquired hypogonadism. The aim of this study was to evaluate the fertility indicators in male patients with β-thalassemia major and intermedia. In this study we evaluated testicular volume, semen parameters and serum FSH, LH, and Testosterone concentrations in 62 male patients in reproductive age, with major and intermedia thalassemia, at a tertiary care hospital in Tehran, Iran. The range of serum ferritin level in our patients was from 182 to 11053 ng/mL (mean 2067 ng/mL). The mean concentration of sperm was 61.04 million per milliliter. The mean volume of right and left testes was 11.4 cc and 11.7 cc, respectively. Those patients who had lower testicular volumes significantly had lower sperm concentration, lower percents of motile and also lower percents of normal morphologic sperms (P=0.04). The frequency of hypogonadism was significantly higher in patients whose testicular volume was lower (P=0.02). Hypogonadism and hypothyroidism were seen in 22.6% and 17.7% of patients, respectively. Patients with hypogonadism had significantly lower ejaculate volume, lower sperm concentration, lower percents of motile and progressively motile sperms and also lower percents of normal morphologic sperms (P=0.001). This study suggests that in thalassemic men, concentrations of serum testosterone, LH, FSH has significant correlation with sperm parameters and testicular volume.