Testes and accessory glands measurements are taken as a potential for male selection. This study was designed to follow up the developmental changes of Chios rams genitalia using ultrasonography, tape and caliper. Twenty rams were allocated into equal four age groups: A (6 months, BW: 19.3+2.8 kg), B (12 months, BW: 28.2+4.8 kg), C (18 months, BW: 34+2.8), and D (24 months, BW: 42.727.5 kg). In each group, the mean values of scrotal circumference (SC), testicular breadth (TB), and diameters of bulbourethral gland (BUG), pars disseminate of prostate (PDP), and seminal glands (SG) were measured and correlated. SC increased rapidly between 6 and 18 months and non-significantly between 18 and 24 months. Similarly, TB increased rashly between 6 and 18 months and slowly between 18 and 24 months. BUG increased slowly between 6 and 18 months and non-significantly between 18 and 24 months. PDP remained constant until 12 months, then increased significantly between 12 and 18 months, to remain constant again between 18 and 24 months. SG increased non-significantly between 6 and 12 months, then increased rapidly between 12 and 24 months. Positive correlations were found between SC, TB and each of BUG, PDP and SG. It could be concluded that male genitalia of Chios rams developed in different patterns between 6 and 24 months age. Ultrasonography assists studying the accessory glands directly in the living animals, which was unattainable before.