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Synthesis and structural studies of double perovskite materials with general formula LaSrBMnO6 (B=Fe、Co),where B is a transition metal,have been reported in several occasions [1-2].They exhibit quite interesting structural,electronic as well as magnetic properties.but they were paid little attention in catalytic field,especially in the relationships between the structure of double perovskites and Catalytic activity of methane combustion,and between the structure of double perovskites and Electrical Conductivity.The double perovskite oxide LaSrBMnO6 (B=Fe、Co) were synthesized by the sol-gel method using ethylene glycol as complex agent (the samples were heated under reduction conditions (5%H2/95%N2 flow) at 1100℃ for 3 h).These samples have been characterized by XRD,TPR,BET,FT-IR,Electrical Conductivity Test.The samples catalytic activity have been tested in methane combustion.Fig.1 shows the XRD pattern of LaSrBMnO6 (B=Fe、Co) measured at room temperature.we conclude that the obtained polycrystalline powders are single phase and the crystal structure of the samples were found to be cubic.We have listed correlative parameters for the samples in Table 1.Fig.2 Catalytic activity of CH4 combustion of the samples at 1100℃,we found LaSrFeMnO6 have a good catalytic activity in methane combustion,which T10(methane conversion of 10 %) and T90 (methane conversion of 90%)are 431 ℃Cand 524℃,respectively.The Catalytic activity of double perovskites LaSrFeMnO6 is near to LaCoO3.The main reason is the structure of LaSrFeMnO6 play important part in activity.We found its XRD patterns is wider,the particle size is decrease,the specific surface area is larger,catalytic activity was enhanced obviously.The electric conductivity was measured.we conclude that the electric conductivity of LaSrCoMnO6 accords with characteristic of n-type semi-conductor going up with the temperature decreasing and the electric conductivity of LaSrFeMnO6 accords with characteristic of p-type semi-conductor going up with the temperature increasing.