The invention provides a method for improving the dyeing fastness of light beige semi-vegetable tanned goat leather; the method comprises the following steps of: carrying out group batching, wringing, grass ash tumbling, shaving and trimming on raw skins conforming to the technical requirements according to the traditional conventional process; and carrying out weighing, first washing, degreasing, second washing, oxalic acid treatment, third washing, chromium retanning, fourth washing, neutralization, fifth washing, dye filling, six washing, fat-liquoring and color fixing, and seven washing on trimmed blank skins. A light beige semi-vegetable tanned goat leather dye manufactured by the method is 1 / 3 of that manufactured by a conventional process without using a color fixing agent in consumption, i.e. the consumption is reduced by 2 / 3; and the absorption rate of waste liquid is high, thereby facilitating environmental protection. Manufactured semi-vegetable tanned goat leather finished products have consistent leather surface color, uniform color, full surface coloration, small color difference among pieces and full, pliable, setting-out and non-wrinkled leather body. The method has the outstanding advantage that the perspiration fastness is also improved while the dyeing fastness of the light beige semi-vegetable tanned goat leather is improved.