Microfilter

The utility model discloses a micro filter which comprises a cylinder body, a through cavity is arranged in the cylinder body, a first piston is arranged at one end of the cavity in a sliding manner, and the other end of the cavity is communicated with a liquid outlet pipe; a filtering layer is arranged at the end, close to the liquid outlet pipe, of the cavity, filtering holes are formed in the filtering layer, and the aperture range of the filtering holes is 0.22-0.45 mu m; a dewatering layer is arranged at one end of the filtering layer away from the liquid outlet pipe. According to the utility model, the water removal layer adsorbs water in a sample, and the filter layer filters out fixed impurities separated out from the sample through the tiny filter holes; besides, the first piston provides power for water removal and filtration of the sample, when the first piston slides towards the liquid outlet pipe, the pressure between the piston and the cavity drives the sample to move towards the liquid outlet p