The invention discloses a methane purification and primary filtration device which comprises a filtration tank, wherein the filtration tank is connected with a methane collection tank; methane is collected from the methane collection tank; generally, a blower is utilized for pumping out the methane in the methane collection tank and then pumping the methane into the filtration tank; the filtration tank comprises a tank body, the tank body is internally provided with a clapboard which divides the tank body into upper and lower parts, and an opening is reserved in the middle of the clapboard; the bottom of the tank body is provided with a gas inlet cavity, the upper side of the gas inlet cavity is provided with a primary filtration chamber, and a secondary filtration chamber is formed above the clapboard. The methane purification and primary filtration device has the beneficial effects that the design is reasonable and the structure is simple; by virtue of arranging the independent gas inlet cavity, the inlet gas is divided into two branches, one branch of gas is discharged by virtue of a gas vent in a spiral gas inlet pipe, and is changed into irregular flow direction to collide and interfere with the other branch of gas so as to achieve a speed reduction effect; a filter screen is internally provided with natural clinoptiloite zeolite which serves as an adsorbent, so that a primary purification and filtration effect for the methane is achieved.