The invention belongs to the technical field of biological medicine, and relates to anti-tumor synergistic drugs, in particular to a synergistic compound drug for tumor treatment composed of one or more ceramides and sorafenib. The compound drug has no obvious cytotoxicity itself, but the tumor cell killing effect can be enhanced remarkably after combined use, and the tumor cell killing effect of sorafenib can be further enhanced by improving the poptotic effect; meanwhile, the dosage of the drug can be reduced, the treatment effect can be improved, and toxic and side effects on the human body can be reduced. The invention further provides a method for using the synergistic compound drug and a pharmaceutical composition thereof, for example, combined administration or sequential usage is adopted to treat liver cancer, kidney cancer, non-small cell lung cancer or thyroid cancer, so as to enhance the tumor killing effect of the drug.