Abstract: Computational formulas of load flow resistance loss of fluid supply system in fully mechanized mining face under circular fluid supply mode were derived through theoretical analysis. Taking fluid supply system of No.1 working face in Huangling Coal Mine as an example, load flow resistance loss distribution at different hydraulic support position in working face was obtained. Pipeline pressure in the fluid supply system was tested through installing one pressure sensor every twenty supports in the working face. Pressure difference approaches the theoretically calculated value, which verifies correctness of the computational formulas of load flow resistance loss. Pump outlet pressure distribution in the fluid supply system was obtained through test under shearer speed of 8 m/min or 12 m/min with single pump or double pumps fluid supply mode separately. Meanwhile, unloading time ratios and loading time ratios of the fluid supply system were counted so as to provide a reference for intelligent control and optimization of fluid supply system during automatic following control.