Layered water injection tool is the core part of layered water injection system,which is of great significance to the development of layered water injection technique.In order to study the influence of different pipeline roughness and flow rate on friction and pressure consumption of crossing bridge short joints of layered water injection tools,Fluent software is used.The simulation results show that the flow rate of crossing bridge short joints of layered water injection tool is 500~2 000 m³/d,the pressure consumption range of the outer pipe is 1.90×10⁴~6.61×10⁵ Pa,and the pressure consumption of the inner pipe is 3.61×10⁵~4.03×10⁶ Pa.When the roughness is constant,the larger the liquid flow would induce greater the local resistance and the greater the friction pressure consumption of the layered water injection tool.The effect of pipeline roughness on friction and pressure loss is small and can be ignored.The above research results can provide the basis for the design and parameter selection of the new layered water injection pipeline.