The invention discloses an application of bilobalide serving as brain-targeting synergists to preparation of drugs or health care products for preventing a brain tumor. Long-term experiment research indicates that bilobalide compounds, particularly, bilobalide, bilobalide extracts, hydroxyl derivatives of the bilobalide, particularly, glucoside, ester and ether derivatives of the bilobalide can effectively facilitate natural drug molecules or chemical drug molecules to enter brain tissues, the natural drug molecules or chemical drug molecules have treatment or health care effect on the brain tumor, the natural drug molecules include total saponins of panax ginseng, ganoderic acid or ganoderan, matrine and podophyllotoxin, the chemical drug molecules include glivec, imatinib, icotinib, teniposide, dacarbazine, nimustine and the like, concentration of the natural drug molecules or chemical drug molecules in the brain tissues is greatly improved when plasma concentration is not improved, curative effect of drugs is effectively improved, and side effects and adverse reaction of the drugs are decreased.