Disclosed is a method of manufacturing a sound absorbing material for a vehicle, which may include: (a) preparing a mixed fiber including an amount of about 55 to 75 wt % of microfiber polyethylene terephthalate staple fiber having fineness of about 0.3 to 0.7 denier, an amount of about 20 to 40 wt % of low-melt polyethylene terephthalate staple fiber having a fineness of about 1 to 3 denier and a melting point of about 100 to 110° C., and an amount of about 1 to 20 wt % of hollow staple fiber having a fineness of about 13 to 17 denier and a diameter of about 38 to 43 μm, based on the total weight of the mixed fiber. The method may suitably further comprise (b) forming a plurality of webs comprising the mixed fiber; (c) forming a web layer comprising a plurality of webs; and (d) forming non-woven felt comprising the web layer.