In this research, the powdery dried chicory roots and pure inulin are used as food additives, separately to improve the functions of the immune system disorders in forty male albino rats through the existing content of inulin. The obtained experimental results after feeding for 42 days showed that the body weight gain, feed intake and feed efficiency ratio of chicory roots (10%) group was the best in comparison to all other groups. Immunoglobulins (IgM, IgG and NO) analyses recorded high significant differences between (-ve) and (+ve) control groups and all the treated groups. The best IgM value (77.692 and 99.612 mg/dL) was recorded for chicory roots 10% and pure inulin 1.0% with significant differences in comparison with (-ve) and (+ve) control group respectively. Histopathological studies showed the liver portal triads were apparently normal with a few round cells infiltration, Kidneys were apparently normal with preserved nephrons histomorphology and apparently normal spleen with preserved lymphoid population of white pulp and normal sinusoids and lympho-reticular network of red pulp in chicory roots (10%) group. The obtained results recommended using chicory roots (10%) in the production of functional and medicinal food to enhance the nutritional quality and the physiological status of the formulated food.