NOVELTY - A metal oxide porous component is obtained by subjecting metal alkoxide and/or its partially hydrolyzed/condensed product to sol-gel reaction in presence of particles of terminal-branched polyolefin copolymer having number average molecular weight of 2.5x 104 or less, obtaining organic-inorganic composite and removing the particles of terminal-branched copolymer from the obtained composite.    USE - Metal oxide porous component is used for catalyst, catalyst carrier, substance carrier, deodorant, membrane filter, separation membrane, insulating film and filler used as substrate and interlayer insulation film of circuit board, anti-reflective film for optical medium, weight-reduction filler, hygroscopic agent, humidity control agent and photocatalyst (all claimed) used for electrode material for dye-sensitized solar cell. Can also be used for solid electrolyte membrane and sustained-release material.    ADVANTAGE - The metal oxide porous component has uniform pore diameter, small volume average particle diameter and excellent mechanical strength, and provides membrane filter having excellent durability and mechanical strength.    DETAILED DESCRIPTION - A metal oxide porous component is obtained by subjecting metal alkoxide and/or its partially hydrolyzed/condensed product to sol-gel reaction in presence of particles of terminal-branched polyolefin copolymer of formula: X1-C(-R1)(-A)-CH(-R2)-X2 having number average molecular weight of 2.5x 104 or less, obtaining organic-inorganic composite and removing the particles of terminal-branched copolymer from the obtained composite.    A=polyolefin chain;    R1,R2=H or 1-18C alkyl, where at least one of R1 and R2 is H;and    X1,X2=linear or branched polyalkylene glycol, where X1 and X2 bonds with hydrocarbyl group through carbon, oxygen, sulfur or nitrogen atom.    INDEPENDENT CLAIMS are included for the following:    (1) manufacture of metal oxide porous component, which involves performing sol-gel reaction of metal oxide precursor chosen from metal alkoxide and/or its partially hydrolyzed/condensed product, metal halide, metal acetate and metal nitrate in presence of particles of terminal-branched polyolefin copolymer, drying the obtained reaction solution, producing organic-inorganic composite and removing the particles of terminal-branched polyolefin copolymer from the composite; and    (2) photocatalyst, which contains the metal oxide porous component and titania porous component.