Intravenous human polyclonal immunoglobulins G (IVIg) were initially used as substitutive therapy for primary and secondary immunodeficiencies then for various autoimmune diseases. More recently they were proposed in organ transplant recipients as they induce a decrease of the anti-HLA antibodies titer in HLA immunized patients. Few retrospective and prospective trials have been performed yet, though they clearly show a beneficial effect of IVIg on kidney graft survival. This paper reviews the different potential mechanisms of action of IVIg their use and potential efficacy in organ transplant recipients.