Abstract: Taking the backfilling mining under villages in Xinyang Coal Mine as the project background, through the rheological test, rheological properties and parameters of high concentration cementation filling slurry were determined. Combining with theoretical calculation formula of filling slurry resistance loss in pipeline transportation, slurry resistance under different ratio was calculated respectively. Finally, the results were validated through the round-pipe experiments. The results show that the yield stress and viscosity coefficient of high concentration cementation filling slurry increase with the increase of the dosage of fly ash and its rheological model can be expressed by Bingham plastic fluid flow pattern; based on Bingham model, theoretical calculation formula of high concentration cementation filling slurry resistance loss was proposed. We use the theoretical calculation formula to calculate the theoretical value of the slurry resistance loss in horizontal straight pipe; by round-pipe experiment, the difference between the test result and the theoretical value is not more than 3%, without blocking phenomenon; the reliability of the theoretical formula was verified in practical application.