The invention discloses a breathing mask with filtering and purifying functions. The breathing mask is composed of a mask and a canister, wherein the mask comprises a mask body, an eye window, an interphone, a breathing valve and a fastener. The breathing mask is characterized by further comprising a double-layer exhalation valve or a multiple-layer exhalation valve composed of two or more exhalation valve plates mutually combined in series; grilles are arranged between the exhalation valve plates and between the exhalation valve plates and the mask body; an air inlet is formed in the bottom of the mask body and connected with the canister through an air guide tube; the canister comprises a first adsorption component, a catalyzing component and a second adsorption component which are stacked both front and back. The removal rate of a catalyst for benzene, toluene, dimethylbenzene, ethylbenzene, styrene, formaldehyde, acetaldehyde and acrolein in air in buildings achieves below 0.05mg/cubic meter, and meanwhile the content of microorganisms in recycle gas is significantly reduced.