The invention provides an automobile exhaust purifier which comprises a shell. A gas inlet pipe is arranged at the front end of the shell. The gas inlet pipe is connected with an exhaust pipe of an automobile through a connecting sleeve, and a gas outlet pipe is arranged at the rear end of the shell. A filtering net is arranged at the inner front end of the shell, a reaction device is arranged atthe inner middle portion of the shell, and an atomizer is arranged at the inner rear end of the shell. A dust collecting box is arranged below the filtering net, and the dust collecting box communicates with space, in front of the filtering net, in the shell. The reaction device comprises multiple upper partition plates and multiple lower partition plates, wherein the upper partition plates and the lower partition plates are sequentially arranged alternately, and the middle space in the shell is divided into a wavy runner through the upper partition plates and the lower partition plates. A reduction catalyst, an oxygen production agent and an oxidization catalyst are sequentially stored in the runner in the airflow flowing direction. A liquid storage tank is arranged above the atomizer, and a Ca(OH)2 solution is arranged in the liquid storage tank. An inlet of the atomizer communicates with the liquid storage tank, a liquid collecting bucket is arranged below the atomizer, and an outlet in the lower end of the liquid collecting bucket is connected with the liquid collecting tank. The purifier can be used for effectively removing harmful components in exhaust.