Abstract: The perovskite-like La_2-xSr_xCoO_4±λ(x=0—1.0)mixed oxides were prepared by the polyglycol gel method, investigated by using the XRD, IR, BET, TPD and chemical analysis methods, and used successfully for CO and C₃H₈ oxidization.In addition, the effects of coefficient x on their structure and catalytic activities of these samples were studied.The results indicate that all La_2-xSr_xCoO_4-λhave K2NiF4 structure, their structure and catalytic activities change regularly with the change of coefficient x.The catalytic activity of LaSrCoO_4-λ is the best among all samples, which can be explained in terms of more mobile lattice oxygen, higher content of Co³⁺, more oxygen vacancies and more chemisorbed oxygen of LaSrCoO_4-λ.