A light guide plate that eliminates haze while obtaining a desired uniformity of luminance to enhance light efficiency. The light guide plate can be used with a backlight unit using the light guide plate and an LCD using the backlight unit. The light guide plate includes an incidence face to allow light emitted from a light source to be incident to the light guide plate, an outgoing face to allow the incident light to exit the light guide plate, a backside face opposite to the outgoing face, and mirror patterns provided at the outgoing face or backside face, and adapted to increase an exiting rate of the light at a low luminance region defined in a vicinity of the light source. The light guide plate is manufactured by a method including a mold machining operation including a prism face milling operation to form, at a mold, a prism face corresponding to a prism face of the light guide plate, and a mirror pattern milling operation to mill the prism face formed at the prism face milling operation using a bit having a predetermined cross-sectional shape, thereby forming mirror patterns at the prism face, and a light guide plate injection-molding operation to mill a molten resin into the mold completely machined at the mold machining operation, thereby injection-molding the light guide plate.