The invention relates to a visible broad-spectrum depolarizing beam splitter. The beam splitter consists of an optical glass substrate and a beam splitting film, wherein the beam splitting film consists of the following 10 film layers sequentially from inside to outside: a 1st layer: a dielectric material Al2O3 film layer; a 2nd layer: a metal material Ag film layer; a 3rd layer: a dielectric material TiO2 film layer; a 4th layer: a dielectric material SiO2 film layer; a 5th layer: a dielectric material TiO2 film layer; a 6th layer: a dielectric material Al2O3 film layer; a 7th layer: a dielectric material MgF2 film layer; an 8th layer: a dielectric material TiO2 film layer; a 9th layer: a dielectric material Al2O3 film layer; and a 10th layer: a dielectric material MgF2 film layer. Through the beam splitter, the processing difficulty is effectively reduced, the processing cost is lowered, and the design production is facilitated; and moreover, the film layers are of good hardness and firmness, the working band is 450-650nm, the permeation-reflection ratio is 45:45, and the difference between component S and component P is less than +/-5%.