This study conducted to evaluate semen quality and plasma testosterone (T), tetra-iodothyronine (T4 ), and triiodothyronine (T3 ) concentrations for different strains of Awassi sheep of different ages in Jordan. Physical traits, semen characteristics and blood samples were assessed in 12 local Awassi rams (6 matures and 6 yearlings) and the 7 crosses of improved Awassi rams (4 matures and 3 yearlings) from the beginning of April until the end of September at the Khanasry Station in Jordan. Local Awassi rams had greater (P<0.01) ejaculate appearance (EA) scale (2.66 ± 0.14 and 2.00 ± 0.19), mass motility (MM) (75.8 ± 1.2% and 70.2 ± 1.6%) and higher (P<0.001) live sperm percent; higher (P<0.05) sperm concentration and (SCN) progressive motility (PM) than crosses of improved Awassi. Local Awassi rams had lower (P<0.001) primary (PAb) and secondary (SAb) abnormal sperm than crosses of improved Awassi. Mature rams had a greater (P<0.05) ejaculate volume (EV), EA scale, SCN and live sperm percent than yearlings. Yearling rams had greater (P<0.001) plasma T3 (2.05 nmol/L) than mature (1.75 nmol/L) rams. Weekly variations were significantly (P<0.01) different from both strains for some of semen characteristics and blood parameters with fluctuations in different trends. This study indicates that cross breeding of local Awassi with improved Awassi did not improve semen quality and quantity of Awassi sheep in Jordan.