Abstract: From birth, the human being and animals are exposed to a continuous stream of microorganisms that have adverse effects on their body conditions and health status. In a global scale, there are many factors affecting the immune status such as systemic disorders, malnutrition, infectious diseases, deficiencies of minerals and trace element including copper, zinc, selenium and iron, protein-energy malnutrition, vitamins deficiency and fetal malnutrition. A total number of 20 diseased sheep, 1-2 years old from different localities had been subjected to this study. The selected animals were thoroughly examined and the results of physical and laboratory investigations were reported. The diseased animals showed the clinical signs of zinc deficiency mainly emaciation, alopecia and parakeratosis of the skin covering the vulva, anus, tail, head and ears. In addition ten clinically healthy sheep were served as control group. Lymphopenia with decreased activity of superoxide dismutase enzyme are characteristic for zinc deficiency. Monocytosis also recorded in such clinical cases, followed by significant decrease in monocytes % after zinc supplementation. In addition, decreased levels of serum total proteins, albumin, globulins and immunoglobulins in such cases were observed. The treatment with zinc improves cellular and humeral immunity. In addition, there was a significant (p<0.05) reduction in the levels of superoxide dismutase enzyme (0.4±0.02) in zinc-deficient sheep. The obtained results of laboratory investigations of zinc deficient sheep revealed that there was a significant reduction in the levels of zinc associated with non significant variations in the levels of copper. Concerning the leucocytic picture the results revealed that there was a significant (p<0.05) reduction in the total leucocytic count and a significant (p<0.05) decrease in lymphocyte % with a significant increase in monocytes % in cases of zinc deficiency when compared with their values in healthy animals. It could be concluded from this study that immune system is extremely affected by several factors. It is observed that micronutrient such as zinc is the major element affecting the immune status in sheep. This elemental deficiency adversely affects the cellular and humeral immune status in sheep.