The invention provides a preparation method for a 
fluoride-free waterproof and 
moisture permeable 
fibrous membrane with a photocatalytic self-cleaning function. The preparation method is characterizedby comprising the steps that step 1, an 
electrospun fiber membrane is prepared, wherein a hydrophilic 
polymer which cannot be dissolved in water is dissolved in a 
solvent to prepare an electrostaticspinning solution, and a 
fiber membrane base material is prepared through electrostatic 
spinning; step 2, the 
fiber membrane base material is dipped in an environmental-friendly 
fluoride-free waterproof agent solution or 
emulsion at the indoor temperature, then pre-dried and baked; step 3, nano-particles with the photocatalytic performance are utilized for conducting 
coating finish on the obtainedelectrospun 
fiber membrane, the obtained 
electrospun fiber membrane is subjected to high-temperature 
drying, and the 
fluoride-free waterproof and 
moisture permeable 
fibrous membrane with the photocatalytic self-cleaning function is obtained. The 
water resistance pressure of the prepared environmental-friendly fluoride-free waterproof and 
moisture permeable 
fibrous membrane is greater than or equal to 100 kPa, the 
water vapor transmission amount of the prepared environmental-friendly fluoride-free waterproof and moisture permeable fibrous membrane is greater than or equal to 15,000 g / m<2> / d, the strength of the prepared environmental-friendly fluoride-free waterproof and moisture permeable fibrous membrane is greater than or equal to 30 Mpa, and the fluoride-free waterproof and moisture permeable fibrous membrane can effectively degrade organic pollutants adhering to the surface of the fluoride-free waterproof and moisture permeable fibrous membrane.