In order to carry out the research on the optimisation of the mix ratio of permeable concrete pavement base layer, orthogonal test method was adopted to study the effects of three factors, namely, porosity, water-cement ratio and aggregate size, on the compressive strength and permeability coefficient of permeable concrete. The test results show that the effect of porosity on the performance of permeable concrete is most significant; when the porosity is 18%~22%, the water-cement ratio is 0.26~0.29, and the aggregate size is 9.5~19.0 mm, the performance of permeable concrete is better, and its compressive strength can reach C25, and the permeability coefficient is more than 6 mm/s. The porous concrete can be used for the construction of pavement, and its compressive strength can reach C25, and the permeability coefficient can reach C25.