The invention discloses a compound catalyst used for chemically catalyzing and oxidizing lactic acid to be derived and converted to produce pyroracemic acid. The compound catalyst is prepared from a mixture of a titanium compound, a nickel compound and a cobalt compound. The titanium compound is one or more of titanium monoxide, titanium dioxide and titanium trioxide. The nickel compound is one or more of dinickel trioxide, nickel nitrate, nickel oxalate, nickel acetate and nickel oxalate. The cobalt compound is one or more of cobalt sesquioxide, cobalt sulfate, cobalt oxalate and cobaltous acetate. Reaction selectivity of the compound catalyst is high, and the yield of pyroracemic acid is increased while the catalytic conversion rate of lactic acid is increased.