Abstract: Rats, mice and hamsters were infected by larvae of A. cantonensis, 52.1% of the fats died 24-35 days postinfection. The main cause of death was the damages in the cerebral blood vessels due to the migration of young adults from the brain to the lungs, which gave rise to severe hemorrhage. Besides, the worms themselves also directly dama-ged the brain tissues.From the 31st day postinfection, the reactions caused by the deposited eggs and the damages in the capillaries of alveoli caused by the moving larvae from the 36th day on led to the infiltration of inflammatory cells and the proliferations of fibrous tissue around.With the course of infection, pathologic changes extended gradually causing failure in respiratory function. That was the main cause of death in the later stage. Death might occur more rapidly if concurrent infections were present.Among rat, mouse and hamster, rat might be the ideal animal model for experimental infection with this worm.The distribution of worms in the CNS of the rats autopsied 24-35 days postinfection was: 52.5% in cerebrum, 19.3% in cerebellum, 11.7% in diencephalon and brain stem, 6.3% in spinal cord, 5.3% in cranial cavity, 4.3% in fissura cerebrocerebellaria and 0.6% in ventricle.