In view of natural sand becoming scarce and the high stone powder content in manufactured sand resulting problems like poor workability and pumpability of concrete prepared,influence of silica fume on workability,mechanical and volume stability of manufactured sand concrete is studied,and the mechanism of the silica fume is analyzed.The results show that suitable amount of silica fume can improve the workability and stability of concrete,solve the high viscosity and bleeding of concrete caused by high stone powder content in manufactured sand,improve the slurry microstructure,and enhance the mechanical and durability performance of concrete,and its 28d dry shrinkage rate is below 400×10-6.When stone powder content in manufactured sand is around 10% and silica fume content is from 6% to 9%,the prepared C50 manufactured sand concrete has good uniformity,and the slurry viscosity value is around 2.5 Pa?s,and bleeding rate is almost zero.Its practical application is satisfactory.