A novel inorganic-organic hybrid [(H(2)en)(7)(C2O4)(2)]n(Pb(4)l(18))n center dot 4nH(2)O has been synthesized by employing an organic anionic-cationic co-template. It shows a new type of perovskite structure, featuring staircase-like inorganic network. The title compound exhibits an intriguing semiconducting property with E-g = 2.47 eV and strong photoluminescence arising from band-edge transitions.