The diameter of straight pipe is not usually exactly the same with the diameter of turbine flow-meter, which effect the K-coefficient of the turbine flow-meter. By choosing CL series and LWGY series turbine flow-meter, the calibration test ,the impact of different diameters of upstream and downstream straight pipe, is carried out on the dynamic fuel flow standard device. The experimental results show that the error introduced from straight pipe can not be ignored, therefore, the use or calibration of turbine flow-meter is required diameter of straight pipe is consistent with the flow-meter.