Intravenous immunoglobulin (IVIG) is an immunomodulating agent that induces beneficial therapeutic responses in children and adults. IVIG is not only used for prophylaxis and therapy of infections in patients with primary and secondary immunodeficiencies associated with defective antibody production, but also used for treatment of patients with systemic inflammatory disorders, autoimmune diseases, and neuroimmunologic conditions. IVIG is generally considered a safe and efficacious therapeutic modality. However, it is associated with certain adverse effects including hematologic complications such as hemolytic anemia, leukopenia, neutropenia, monocytopenia, disseminated intravascular coagulation, and changes in blood rheology. Venous and arterial thrombotic complications can also occur following treatment with IVIG in high risk patients. It is very important for clinicians to have the knowledge of those adverse events profiles; and this article summarizes hematologic toxicities associated with IVIG therapy reported in the literature; and describes strategies for their identification and management.