A propylene copolymer resin composition capable of improving softness while maintaining excellent strength properties when preparing nonwoven fabrics, and a method for preparing the same are provided. The propylene copolymer resin composition includes a propylene-ethylene copolymer having an ethylene content of 12 to 18 wt % in the propylene-ethylene copolymer and a propylene-1-butene random copolymer satisfying the following conditions (i) to (iv), wherein (i) 1-butene content of 1 to 5 wt % in the propylene-1-butene random copolymer, (ii) molecular weight distribution of 2.4 or less, (iii) storage modulus of 1200 MPa or less at 25° C., and (iv) phase angle of 5.5° to 8° at a glass transition temperature, and wherein a weight ratio of the propylene-1-butene random copolymer to the propylene-ethylene copolymer is 80:20 to 99:1.