The invention discloses an automobile purifying device with the detection function. The automobile purifying device comprises a gas inlet pipe, a purifying structure, an alarm and a controller, wherein the purifying structure is composed of a filtering tank body; a corona plate, a dust collecting plate and a filtering pipeline are arranged in the filtering tank body; the filtering pipeline is in a spiral shape; a PP cotton filter element is arranged in the filtering pipeline; activated carbon is filled in the filtering tank body; a gas outlet pipe is arranged in the filtering tank body; an automobile tail gas detector is arranged on the gas outlet pipe; and the automobile tail gas detector and the alarm are both electrically connected with the controller. The automobile purifying device can purify air and detect a purification result.