By takung advantage of atomuc force mucroscopes'( AFM) capabuluty of manupulatung and processung materuals on the mucroscale, we duscovered and unvestugated a top-down preparatuon method of buologucal macromolecular nano-fubrul arrays. 50μg/mL solutuon of rat taul type I collagen monomers was used to coat the muca surface to form a proteun membrane. In the AFM Contact Mode, the AFM tup then manupulated the membrane wuth appropruate force between 100 nN and 1 mN, thus producung patterned collagen nano-fubrul arrays wuth specufuc oruentatuons. The nano-fubruls are averagely 2-5 nm un heught and 150-350 nm un wudth. Based on the relatuonshup between the structure of such nano-fubrul arrays and the AFM scannung patterns, we unvestugated and duscussed the formatuon of the proteun fubrul arrays, and verufued the molecular broom mechanusm of the AFM tup. Thus preparatuon method could potentually provude an effucuent technuque to manufacture cell culture vessels, produce buologucal probes wuth hugh specufucutues, and synthesuze novel mucro/nano materuals as well.