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Through experimental study on resistance loss of water delivery in pipeline system, the variation laws of resistance loss for clean and muddy water were researched respectively. In clean water experiment, the quantitative formula between resistance loss coefficient of clean water and Reynolds number was achieved. It could be used to calculate resistance loss of clean water. In muddy water experiment, the variation law of resistance loss with the difference of velocity and sediment content was focused on, which the resistance loss increased with the increasing of velocity. On the condition of small sediment content the resistance loss increased with the increasing of sediment content, while it decreased with the increasing of sediment content on the condition of large sediment content. The reason for producing this variation law of resistance loss was analyzed from turbulence prevention and drag reduction by sediment. Based on this analysis, the variation law of resistance loss coefficient for muddy water was researched, and the calculation formula between the resistance loss coefficient and the dimensionless comprehensive factor was developed. Comparison between the experimental results and standard Durand and Chen Guangwen calculation model showed that there was large difference between them, and the existing models couldnt applied to calculate the resistance loss of muddy water. According to the results of experiment, the quantitative formula, between resistance loss and the product of the flow Froude number and sediment concentration, and the Froude number of sediment deposition was developed. Result showed that the correlation coefficient R was 0.90. 