SUMMARY: The American Cancer Society estimates that about 71,850 people will be diagnosed with Non-Hodgkin Lymphoma (NHL) in the United States and about 19,800 individuals will die of this disease. Approximately 20% of all NHLs are Follicular Lymphomas. Follicular Lymphoma is the most indolent form and second most common form of all NHLs and they are a heterogeneous group of lymphoproliferative malignancies. Advanced stage Follicular Lymphomas are not curable and as such prolonging Progression Free Survival (PFS) and Overall Survival (OS) while maintaining quality of life (QoL), has been the goals of treatment intervention. Asymptomatic patients with FL are generally considered candidates for “watch and wait” approach, whereas those with B symptoms (fever, night sweats, and weight loss), painful lymphadenopathy/splenomegaly, organ compromise and cytopenias are generally considered candidates for therapy. Follicular Lymphoma International Prognostic Index (FLIPI) is of prognostic value and is used to help with treatment choices. Several studies have been underway evaluating the association between serum Vitamin D levels and cancer. Previously published studies have shown a relationship between Vitamin D deficiency and poor outcomes in patients with Diffuse Large B Cell Lymphoma and Chronic Lymphocytic Leukemia. The beneficial effects of Vitamin D in malignancies has been attributed to its antiproliferative and antiangiogenic properties, as well as its effects on cell differentiation, promotion of apoptosis and its ability to decreases oxidative DNA damage. Further, macrophages play an important role in the human body’s response to therapy with monoclonal antibodies, an integral part of Follicular Lymphoma therapies and low serum Vitamin D levels may interfere with macrophage function and this may explain poor outcomes in some Follicular Lymphoma patients with low Vitamin D levels