The invention discloses a method of preparing an antibacterial anti-
pollution ultrafiltration membrane by adopting a silver-loaded nano 
composite material. The method comprises the following steps: preparing a nano material water dispersion solution, adding trihydroxymethyl aminomethane and 
dopamine hydrochloride, stirring and reacting for 2 to 12 hours, centrifugally washing, then 
drying to obtain a polydopamine-modified nano material; preparing a 
mixed solution containing the polydopamine-modified nano material, a silver-
ammonium solution, a stabilizer and water, stirring for 2 to 12 hours, centrifugally washing, and then 
drying to obtain the silver-loaded nano 
composite material; dispersing the silver-loaded nano 
composite material in an 
organic solvent, adding a membrane material, stirring, completely dissolving the membrane material, and standing to obtain a membrane 
casting solution; and scraping the membrane 
casting solution into a flat membrane by utilizing a flat membrane scraping 
machine, immersing in a coagulating bath, and carrying out a 
phase conversion to obtain the antibacterial anti-
pollution ultrafiltration membrane. The 
ultrafiltration membrane has good hydrophilia, durable antibacterial performance and excellent anti-
pollution performance, has good antibacterial and sterilization effect for colibacillus, 
bacillus subtilis and the like; moreover, the 
silver nano particles stably exist in the antibacterial anti-pollution ultrafiltration membrane.