This paper researches the preparation technology of C50 box girder concrete with mechanism sand and natural river sand,according to the engineering design requirements of C50 box girder concrete of Guangxi Wuliu highway engineering,and combining with the corrosion characteristics of the local environment.Comparing and analyzing the mechanical properties,crack resistance,durability performance and volume stability of the two kinds of concretes,we draw the conclusion that the working performance of C50 sandstone-mechanism sand box girders concrete is similar to that of the concrete with natural river sand;the physical performance of the former such as compressive strength,axial compressive strength and elastic modulus are better than that of river sand concrete.Selecting appropriate dosage of the gelled material and the admixture,we can proportion the C50 sandstone-mechanism sand box girder concrete which has better durability performance and volume stability than the river sand concrete.