Objective To investigate the regulatory effects of icariin (ICA) combined with the Panax notoginseng saponins (PNS) on immunological function in mice and provide some experimental evidences for the combination mechanism improving the spatial learning and memory abilities of Alzheimer's disease (AD) animal model. Methods Based on serum pharmacological method, the ICR mice were individually ig administrated with ICA+PNS [(40+320), (80+640), and (160+ 1 280 ) mg/kg] or ICA (80 mg/kg), and PNS (640 mg/kg) only for 7 d. Drug-containing serum was prepared and effects on spleen lymphocyte proliferation of Bable/c mice induced by concanavalin-A (ConA) or lipopolysaccharide (LPS) and on interleukin-2 (IL-2) secretion were observed in vitro. Meanwhile, the immunological organ indexes of treated mice were evaluated. Results Drug-containing serum of ICA+PNS [(80+640) and (160+ 1 280 ) mg/kg] could improve the spleen lymphocyte proliferation induced by ConA (P0.05). Drug-containing serum of ICA+PNS [(80+640) and (160+ 1 280) mg/kg] could improve IL-2 production (P0.05), respectively. Conclusion ICA combined with PNS could improve immunological function selectively and promote T cell function in mice.