The invention relates to a method for preparing the drug used to prevent expressed hydrophobia and treat the early hydrophobia. The invention uses the expression corns, composite dual-chain low-disturbance RNA (siRNA) or the recombined carrier virus with siRNA expression element as the agent, via the RNA disturbance effect that baffling the combination of hydrophobia virus structure protein mRNA to treat the expressed hydrophobia. The invention can be used to replace present antirabies serum or immune globulin, to avoid side ffect. The inventive drug can be injected via vein or cerebrospinal fluid, to baffle the increment of cerebrospinal fluid in the central nervous system.