The invention discloses an automobile three-way catalyst. A calabash-shaped carrier outer cover is arranged on the outer wall of the automobile three-way catalyst. An oblique opening bypass hole is formed in the outer wall of a carrier, powdery or particle-shaped solid pollutants conveniently fall into the calabash-shaped carrier outer cover, and accordingly solid pollutants left in the carrier are reduced. Meanwhile, the waistline position of the calabash-shaped carrier outer cover is connected with a ventilation hole, the ventilation hole is connected with an air blowing pipeline, the air blowing pipeline communicates with an air outlet hole in a flow guiding pipe, the catalysis efficiency of unit area is increased, meanwhile, airflow uniformity is improved, and a favorable function is achieved for reducing flow resistance; and when the carrier is blocked, most of airflow is discharged to the atmosphere through the bypass hole, and accordingly damage to an automobile due to increasing of backpressure is reduced.