Mad cow disease, also known as Creutzfeldt-Jakob disease, is a subacute progressive neurological disease caused by prion protein infection of the human body. The prion protein in normal human body is α-helix structure, water-soluble and sensitive to protease, under the action of some unknown protein α-helix can be transformed into β-folded structure, β-folded prion is not sensitive to protease, poor water-soluble, and heat-stable, it can be aggregated with each other, and finally form amyloid fibril precipitation and cause disease. Patients with mad cow disease usually have vacuoles in brain cell tissues, astrocyte hyperplasia, amyloid protein fibers found in the brain autopsy, and accompanied by systemic symptoms, characterized by a long incubation period, high mortality rate, and high infectiousness, in which the more vacuoles appear, indicating that it is closer to the advanced stage of the disease. The early symptoms of the disease are varied, and the disease progresses at a rapid rate, the most typical being rapidly progressive dementia. At present, there is no effective treatment for mad cow disease, the main measure is to do a good job of prevention.