Abstract: This research was designed study the relation between vitamin D and selenium status as well as glutathione peroxidase activity as one of the antioxidant systems that may be a part of the immunodeficiency syndrome in rickets. The study was conducted on 33 patients diagnosed as active rickets on clinical, laboratory and radiological basis. Thirty age and sex matched apparently healthy infants and children were chosen to serve as controls. All studied infants and children were subjected to blood work to assess Complete Blood Picture (CBC), serum levels of 1, 25 (OH) 2 D, Calcium (ca), phosphorus (P), alkaline phosphatase (ALP) and selenium (Se) as well as Glutathione Peroxidase (GPX) enzyme activity in the whole blood. Patients were given intramuscular injection of Vitamin D in a shock therapy (600000 IU every 2 weeks for 3 doses) as well as oral Ca supplementation (800-1000 mg elemental Ca/day). These patients were reassessed clinically, radiologically and for the same laboratory parameters at 2 and 6 weeks after the start of treatment. The study revealed that the mean levels of serum Ca, P, active vitamin D, Se and GPX enzyme activity were significantly lower (p<0.001) compared to control, while the mean serum level of ALP was significantly higher (p<0.001) in rachitic patients at diagnosis compared to controls. The mean serum Ca and Se levels as well as GPX activity showed a significant increase after 2 weeks (p<0.001) and a further significant increase after 6 weeks of treatment compared to levels at diagnosis (p<0.001). On the contrary, the mean level of ALP showed a significant decrease after 2 weeks (p<0.001) and a further significant decrease after 6 weeks of treatment compared to levels at diagnosis (p<0.001). The serum active vitamin D levels had significant positive correlations with serum levels of Ca, Se and GPX activity (p<0.001) and negative correlation with ALP levels. Similarly, serum Se level showed significant positive correlation with GPX activity (p<0.001) and significant negative correlation (p<0.05) with serum ALP levels. From the results of this study we can conclude that, patients with active rickets have evidently lower serum selenium levels which may be partly due to lack of absorption as a result of deficient vitamin D or as a part of multiple nutritional deficiency syndromes. Hence, the study recommends not only supplementing vitamin D and Ca but also Se, as it is mandatory for the promotion of the antioxidant activity of GPX with subsequent improvement of immune status in rachitic patients.