In the last two or three decades, physical activity (PA) has gained increasing recognition as being essential for maintaining good health and improving quality of life for all ages. To evaluate the nutritional status, oxidant/antioxidant, and inflammatory markers, in sports adolescents, a cross sectional study has done in west Algeria. A total of 110 athletes adolescents from special sport classes, aged 11-17 years, were compared to a non athletes group (n=60). Blood pressure, anthropometric and serum parameters were measured. Daily energy intake (DEI) was estimated using 24 hours recall, followed by a 3-days record. Energy expenditure (EE) was evaluated by the International Physical Activity Questionnaire-short form (IPAQ-S). Oxidant/antioxidant and inflammatory markers were determined. An increase in body weight and height (p<0.001) was noted in athletes compared to non athletes. DEI was similar in both groups, whereas EE was higher in athletes than non athletes (p<0.001). Serum triacylglycerol (TG) values were lower in athletes group than in non athletes (p<0.05). Enhanced values were observed in glutathione peroxidase (GPx) (p<0.001), and superoxide dismutase (SOD) (p<0.05) activity, and tumor necrosis factor-α (TNF-α) (p<0.01) in athletes compared to non athletes. Significant relationships were found between height, weight, albumin, GPx, TNF-α, IL-1, and EE. Significant associations were noted between GPx (OR=0.14; 95% CI 0.03, 1.05), inflammatory markers TNF-α (OR=0.47; 95% CI 0.28, 0.80), IL-1 (OR=1.17; 95% CI 0.28, 0.80) and physical activity. Significant relationships were found between weight (P < 0.001), height (P < 0.01), albumin, GPx, IL-1, TNFα (P < 0.05) and EE. In spite of inadequate DEI in athletes adolescents, beneficial effect of sport is observed by lowering serum TG concentrations. However, more research in this area is warranted to clarify sport nutrition needs to provide better and healthy nutritional guidance to young athletes.