In order to further improve oil recovery of maturing oilfield by water flooding，the flow characteristics and oil displacement characteristics of the formation water and hexadecyl hydroxypropyl sulfo betaine（HHSB）solution with different salinity in low permeability porous media were analyzed by indoor physical simulation experiments. The experimental results showed that the surface action of low salinity formation water（or surfactant solution）and rock was stronger than that of high salinity and the flow resistance of low salinity formation water and surfactant solution in low permeability porous media was smaller than that of high salinity formation water and surfactant solution. The wetting contact angles of low salinity（4700 mg/L）formation water on the surface of the rock was 83°，and that of high salinity（47000 mg/L）formation water on the surface of the rock was 84.5°. At the condition of low salinity，the adsorption loss of HHSB with 3000 mg/L mass concentration on the rocks surface was 23.33%，while at the condition of high salinity，it was 16.73%. After adsorption on the rock surface，the interfacial tensions between low salinity HHSB solution and crude oil was 0.0045 mN/m，and that of high salinity HHSB solution and crude oil was 0.008 mN/m. Besides，the EOR experimental results showed that high salinity water flooding recovery and low salinity water-flooding recovery was 32.5% and 33.8%，respectively. After high salinity water flooding，the subsequent low salinity water flooding，high salinity HHSB solution flooding，and low salinity HHSB solution flooding could make oil recovery increased by 1.3%，6.2%，and 8.2%， respectively. After low salinity water flooding（oil recovery being of 33.8%），the subsequent low salinity HHSB solution flooding could make oil recovery increased by 7.3%（total oil recovery being of 41.1%）. It was known that low salinity water flooding and the subsequent low salinity surfactant solution flooding could improve oil recovery to the best.