NOVELTY - A white laminated polyester film comprises polyester layer (B) having voids, and polyester layer (A) laminated at least on one surface side of layer (B), where laminated film has following features: e.g. layer (A) has thickness of 5-15 mu m, contains particles with refractive index of greater than or equal to 2.0 in 3-7 wt.% of layer (A), where particles are rutile type titanium dioxide particles, produced by chlorine process, amount of particles having refractive index of greater than or equal to 2.0 contained in layer (B) is less than or equal to 2 wt.%, and layers are formed from resin having polyethylene terephthalate as basic structure.    USE - As white laminated polyester film for a reflecting sheet, which is a rear reflecting sheet of a backlight for a liquid crystal display (claimed), a reflecting sheet of a backlight device and a lamp reflector for image display, a reflecting sheet of a lighting instrument, a reflecting sheet for a lighting signboard, and a rear reflecting sheet for a solar cell.    ADVANTAGE - The polyester film that has a laminated structure, is excellent in reflecting property and concealing property, and is high in productivity. The film is not easily broken when the film is produced, and is high in productivity.    DETAILED DESCRIPTION - A white laminated polyester film for a reflecting sheet comprises a polyester layer (B) containing voids in it, and a polyester layer (A) laminated at least on one surface side of the layer (B), where the laminated polyester film has the following features (1) to (7): (1) polyester layer (A) has a thickness of 5 to 15 mu m, (2) polyester layer (A) contains in it particles having a refractive index of greater than or equal to 2.0 in an amount of 3 to 7 wt.% of the polyester layer (A), where the particles having a refractive index of greater than or equal to 2.0 are titanium dioxide particles, mainly of rutile type, produced by a chlorine process, (3) the thickness of the polyester layer (B) is greater than or equal to 150 mu m, (4) the amount of particles having a refractive index of greater than or equal to 2.0 contained in the polyester layer (B) is less than or equal to 2 wt.% of the polyester layer (B), (5) the polyester layer (B) contains in it a resin which is not soluble in polyester resin in an amount of 12 to 25 wt.% of the polyester layer (B) and optionally the polyester layer (B) contains inorganic particles having a refractive index less than 2.0 in an amount of 30 to 50 wt.% of the polyester layer (B), and (6) polyester layer (A) and polyester layer (B) are formed from at least one resin having polyethylene terephthalate as its basic structure, and (7) polyester layer (B) contains a copolymerized resin of polyalkylene glycol and a polyester resin made from 2-6C aliphatic diol component and terephthalic acid, and the amount of the copolymerized resin is 0.05 to 10 wt.% based on the weight of polyester layer (B).