The invention discloses a mouth mask or face mask or mask capable of effectively preventing PM2.5. PM2.5 can be effectively blocked, high breathability can be kept, and the filter effect and breathing comfort can be kept at the same time in the use process of the product. A hollow fiber type capillary tube film with the filtering precision of 0.01 micrometer to 2.5 micrometers is used for replacing a traditional flat plate type and tube type filter material, non-woven cloth and the like, and the filter area far larger than that of a traditional mouth mask is obtained. Under the condition of ensuring effective separation of PM2.5 particles, the breathability of the mouth mask is greatly improved, and according to the protection mask, the functions of soothing breathing, preventing wind, dust and bacteria and the like can be achieved.