A thermoplastic resin composition comprising: 100 parts by weight of a base resin comprising 30 wt% to 70 wt% of a rubber-modified vinyl graft copolymer, 1 wt% to 15 wt% of a large-diameter rubber polymer having an average particle diameter of 3 μm to 8 μm, as measured according to the description using a particle size analyzer and 25 wt% to 65 wt% of an aromatic vinyl copolymer resin; and 0.1 to 10 parts by weight of fine polyorganosilsesquioxane particles having an average particle diameter of 0.1 μm to 10 μm, as measured according to the description using a particle size analyzer wherein the rubber-modified vinyl graft copolymer is prepared by graft polymerization of a monomer mixture comprising an aromatic vinyl monomer and a vinyl cyanide monomer to a rubber polymer having an average particle diameter of 100 nm to 600 nm, as measured according to the description using a particle size analyzer, wherein the large-diameter rubber polymer is present in the form of a rubber-modified aromatic vinyl copolymer resin prepared through continuous solution polymerization of a rubber polymer having a viscosity of 150 mPa.s (cP) or more in a 5 wt% styrene solution, an aromatic vinyl monomer, and a monomer copolymerizable with the aromatic vinyl monomer, wherein the thermoplastic resin composition has a gloss of 5% to 25%, as measured on a 1.5 mm thick specimen at an angle of 60° in accordance with ASTM D523, and wherein the thermoplastic resin composition has a color variation (ΔE) of 0.5 to 3.0, as calculated by Equation 1 based on initial color values (L0*, a0*, b0*) measured on an injection-molded specimen having a size of 50 mm× 90 mm× 3 mm using a colorimeter and color values (L1*, a1*, b1 *) of the specimen measured using the colorimeter after weathering testing for 2,000 hours in accordance with ASTM D4459, Color variation Δ E = _ ΔL * 2 + Δa * 2 + Δb * 2 where ΔL* is a difference (L1*-L0*) between L* values before/after weathering test; Δa is a difference (a1*-a0*) between a* values before/after weathering test; and Δb is a difference (b1*-b0*) between b* values before/after weathering test. 100 parts by weight of a base resin comprising 30 wt% to 70 wt% of a rubber-modified vinyl graft copolymer, 1 wt% to 15 wt% of a large-diameter rubber polymer having an average particle diameter of 3 μm to 8 μm, as measured according to the description using a particle size analyzer and 25 wt% to 65 wt% of an aromatic vinyl copolymer resin; and 0.1 to 10 parts by weight of fine polyorganosilsesquioxane particles having an average particle diameter of 0.1 μm to 10 μm, as measured according to the description using a particle size analyzer wherein the rubber-modified vinyl graft copolymer is prepared by graft polymerization of a monomer mixture comprising an aromatic vinyl monomer and a vinyl cyanide monomer to a rubber polymer having an average particle diameter of 100 nm to 600 nm, as measured according to the description using a particle size analyzer, wherein the large-diameter rubber polymer is present in the form of a rubber-modified aromatic vinyl copolymer resin prepared through continuous solution polymerization of a rubber polymer having a viscosity of 150 mPa.s (cP) or more in a 5 wt% styrene solution, an aromatic vinyl monomer, and a monomer copolymerizable with the aromatic vinyl monomer, wherein the thermoplastic resin composition has a gloss of 5% to 25%, as measured on a 1.5 mm thick specimen at an angle of 60° in accordance with ASTM D523, and wherein the thermoplastic resin composition has a color variation (ΔE) of 0.5 to 3.0, as calculated by Equation 1 based on initial color values (L0*, a0*, b0*) measured on an injection-molded specimen having a size of 50 mm× 90 mm× 3 mm using a colorimeter and color values (L1*, a1*, b1 *) of the specimen measured using the colorimeter after weathering testing for 2,000 hours in accordance with ASTM D4459, Color variation Δ E = _ ΔL * 2 + Δa * 2 + Δb * 2 where ΔL* is a difference (L1*-L0*) between L* values before/after weathering test; Δa is a difference (a1*-a0*) between a* values before/after weathering test; and Δb is a difference (b1*-b0*) between b* values before/after weathering test.