The invention relates to an automobile tail gas purifier, which comprises a converter and a honeycomb fiber purifier, wherein the converter is connected with an automobile tail gas exhaust pipe, the honeycomb fiber purifier is connected with the converter, a pipeline which is connected with the honeycomb fiber purifier is led to a water filtering purifier, the water filtering purifier is separated into four sealing tanks which are four independent spaces and are mutually communicated, common water is injected into the sealing tanks, the water is injected via a water inlet at the upper part of each sealing tank, and is drained via each water drain valve at the lower part of each sealing tank, each sealing tank is connected with a gas suction pump in a tail gas purifier tank through a pipeline, suction force is generated through the running of the gas suction pump, tail gas exhausted by an automobile is sucked into the honeycomb fiber purifier, particles generated when exhausting the tail gas of the automobile are filtered and removed by the honeycomb fiber purifier, and the filtered tail gas enters the four sealing tanks, which are filled with water and are mutually communicated, via pipelines, so harmful gases, residual particles and heat amount in the tail gas of the automobile can be filtered by water.