The invention belongs to the technical field of microbial remediation, and particularly provides a petroleum pollution remediation compound microbial agent and a preparation method thereof. By means of microbial cell life metabolism activities of a micrococcus luteus bacterium suspension, a bacillus pumilus bacterium suspension, an acinetobacter calcoaceticus bacterium suspension and a pseudomonasaeruginosa bacterium suspension, petroleum in the environments such as contaminated soil, oil sludge sand and drilling cuttings is degraded, so that the purpose of remediation of petroleum contaminated soil, oil sludge and other pollutants is achieved. The petroleum pollution remediation compound microbial agent and the preparation method thereof are applied to bioremediation technology of petroleum pollution, have the advantages that the process is safe, the destruction is small, the effect is good, the operation is simple, and secondary pollution is not prone to happening to the environment, and meanwhile, the bioremediation technology can easily achieve scale-up and in-situ implementation.