A method for manufacturing netted dots on a light guide plate is disclosed, including: engraving, on a surface of a metal plate with a preset roughness, a female mould or a male mould corresponding to a shape of the netted dots on the light guide plate; coating the metal plate onto a surface of a roller; heating the roller so that a temperature of the metal plate rises to a preset temperature; adjusting a distance of a center of the roller in relation to a light guide plate feeding passage so that the metal plate applies a preset pressure onto the light guide plate to be machined; and making the light guide plate to be machined pass through the light guide plate feeding passage, wherein the metal plate transfer-prints a shape of netted dots of the female mould or the male mould onto the light guide plate to be machined at a preset pressure and a preset temperature to form the netted dots on the light guide plate. A device for manufacturing netted dots on a light guide plate is also disclosed.