In order to give full play to the particle filling advantage of desert sand and improve the mechanical properties of desert sand concrete, this paper carried out an experimental study on the mix proportion design method of polyvinyl alcohol fiber reinforced desert sand concrete based on Dinger-Funk close-packing theory. Firstly, applying the Dinger-Funk close-packing theory, the optimized sand rate is 42%, the optimized desert sand mass replacement ratio is 10%, 20% and 30%, the concrete aggregate particle gradation is improved, the fineness modulus of mixed fine aggregate is reduced from 3.27 to 2.92, 2.81 and 2.71, and the effective porosity is reduced from 2.50% to 1.65%, 1.45% and 1.51%, respectively. Secondly, the orthogonal test method was used to study the effects of water-cement ratio, desert sand mass replacement ratio, and the volume dosage of polyvinyl alcohol fiber on the workability, compressive strength, splitting tensile strength and flexural strength of concrete. The results show that, with the increase of desert sand mass replacement ratio and fiber dosage, the workability of concrete firstly increase and then decrease, and the compressive strength, splitting tensile strength and flexural strength show the trend of firstly increasing and then decreasing. Considering the test results of the workability and mechanical properties, the optimal mix proportion of C30 polyvinyl alcohol fiber reinforced desert sand concrete is determined to be 0.45 water-cement ratio, 20% of desert sand mass replacement ratio, and 0.10% of polyvinyl alcohol fiber volume dosage.