A meltblown method for producing nonwoven fabrics with hygroscopic metastatic feature. Firstly, fuse prepared bio-polyamide 6,10 into a melt, then extrude, and blow the melt out spinnerets to form natural bio-polyamide 6,10 filaments laid onto a conveyer to form a substrate fibrous web. Secondly, blend and dissolve prepared pulp by putting N-methylmorpholine N-oxide (NMMO) dissolving solvent, and dehydrate it to form dope, then extrude and blow the dope out spinnerets to form natural cellulose filaments laid up over existing fibrous web of bio-polyamide 6,10 on the conveyer so that a fibrous composite of the bio-polyamide 6,10 and natural cellulose in overlaid lamination is formed thereon. Finally, coagulate and regenerate the fibrous composite of the bio-polyamide 6,10 and natural cellulose by means of ejecting mist aerosol of water, and convert it into nonwoven fabric with hygroscopic metastatic feature by orderly applying post treatments of hydro-entangled needle punching, drying, winding-up processes.