NOVELTY - A resin molded product containing resin composition containing silicon-containing compound (a) and silicon-containing polymer (b) is contacted with transition metal salt solution or suspension liquid, and the counter-anion of transition metal salt solution or suspension liquid coordinate with the silicon atom of silicon-containing polymer (b), to form transition-metal microparticles on the resin molded product and/or in the resin molded product. Thus, surface treatment method of resin molded product is carried out.    USE - Surface treatment method of resin molded product such as resin film used for producing surface-treated resin molded product (claimed) used in electroconductive material for wiring of large-sized apparatus, circuit board, semiconductor, solar cell, electromagnetic shield material, mobile telephone, portable apparatus, medical devices, motor vehicle and micro-machine. Can also be used in magnetic material and ornament.    ADVANTAGE - The method provides surface-treated resin molded product having excellent electroconductive property, antistatic property and external appearance.    DETAILED DESCRIPTION - A resin molded product containing resin composition containing silicon-containing compound (a) and silicon-containing polymer (b) is contacted with transition metal salt solution or suspension liquid, and the counter-anion of transition metal salt solution or suspension liquid coordinate with the silicon atom of silicon-containing polymer (b), to form transition-metal microparticles on the resin molded product and/or in the resin molded product. Thus, surface treatment method of resin molded product is carried out. The silicon-containing compound (a) is of formula: R1-(Si(-R3)2-X1)m-Si(-R2)2-R2 (1), (R5-Si(R5)2-O)a-Si-(r)b (2) and/or (3).    R1=group having multiple bond chosen from vinyl, allyl, isopropenoxy or phenyl ethynyl;    R2-R5=R1, H, methyl, ethyl, methoxy, ethoxy or phenyl;    X1=coupling group chosen from -O-, -NH-, -CH2- or -CH2CH2-;    m=0-2;    X2=(-O-) or -NH-;    n=3-5;    r=H, methyl, ethyl, methoxy, ethoxy or phenyl;    a=3-4;    b=0-1;and    a+b=4.