The invention provides a permeable additive for permeable concrete. The permeable additive is characterized in that the permeable additive contains non-wood plant fibers having the capillary permeable function, and raw materials of the permeable additive are composed of, by weight, 50-70 parts of the non-wood plant fibers, 25-35 parts of cellular materials, 3-5 parts of hydrosol, 0.8-1.2 parts of dispersant, 0.6-1.0 parts of water reducer and 0.5-1.0 parts of an active agent. The non-wood plant fibers serve as the main composition body of the concrete additive, and modification treatment is conducted, so that the porosity, water permeation amount and hydrophilicity of the non-wood plant fibers are improved, when the permeable additive is used for preparing the permeable concrete, no or few coarse aggregate can be used, after the permeable additive and the concrete form a firm entirety, the porosity and water permeation amount of the permeable concrete are improved, meanwhile, strength and abrasion resistance of the concrete are guaranteed, and the permeable additive can be applied to high-loading road concrete such as urban rods and expressways.