Objective To examine the potential application of a non-viral genecarrier, water soluble lipopolymer (WSLP) for delivering siRNA targeting N-methyl-D-aspartate receptor 1 (NMDAR1) in vitro. Methods WSLP was complexed with siRNA designed to inhibit NR1 expression. Following serum stability and cytotoxicity observation, WSLP/siRNA (scrambled siRNA as a control ) complexes were transfected in PC12 cells and then siRNA delivery efficiency of the complexes was evaluated by gene expression level assay using reverse transcriptive polymerase chain reaction （RT-PCR） and western-blot technique. Results WSLP protected siRNAs from enzymatic degradation in serum conditioned media, and the complexes of WSLP/siRNA had little cytotoxicity to cultured PC12 cell. NMDAR1 expression of PC12 cell was efficiently inhibited by WSLP/siRNA complexes, while complexes of WSLP with scrambled siRNA (0.64±0.13，4.32±1.09) did not show this inhibitory effect compared to unmodified siRNA (0.69±0.18,4.36±1.02) neither by transcriptional level nor protein level. WSLP/siRNA complexes reduced NR1 transcriptional level by 50%(0.35±0.21)and protein level by 55%(1.96±0.48) when compared to unmodified siRNA. Conclusion Our data suggest that Water soluble lipopolymer can deliver siRNA targeting NMDA receptor 1 in vitro efficiently and safely.