Polyamidoamine dendrimers using inositol as a core were designed, synthesized andcharacterized. The electrostatics interaction of PAMAM dendrimer with DNA causes the condensationof DNA to form DNA/dendrimer complexes. The sizes of complexes prepared from dendrimerG6 and pRE Luc at N/P ratio 10︰1 range from 80 to 300nm. Dendrimers G3 G6 are able toefficiently deliver pRE Luc and pSV-gal gene into HeLa and HEK 293 cells. The transfectionefficiencies of G5 and G6 are much higher than that of poly L-lysine (PLL) and comparable to that ofthe commercial branched polyethylenimine (PEI, Mw 25000), whereas the cytoctoxicities of G5 andG6 are lower than that of PLL.