To determine the pipe pressure drop characteristics in the coarse aggregate paste backfill（CPB）pro? cess. An industrial-scale loop test on the transportation characteristics of CPB was carried out. The actual rheological parameters of CPB are obtained by fitting the Buckingham equation to the loop test data，and the resistance equation was established based on the fluidity test. The response surface method（RSM-BBD）was used to analyze the trans? portation behavior of the CPB，and the effects of single-factor and multi-factor coupling on the pressure loss were ob? tained，respectively. Finally，RSM-BBD was used to optimize the pipeline transportation parameters of CPB. The re? sults show that the rheological parameters obtained by the rheological test were generally larger than those obtained by the loop test，where the differences in yield stress and plastic viscosity between the two are 10.4%~12.2% and 21%~32.8%，respectively. Response surface analysis showed that the sensitivity of a single factor on pressure loss was as follows concentration > pipe diameter > flow rate. And it was found that the interaction between factors had a significant effect，in which the interaction between mass fraction and pipe diameter played a decisive role. Taking the actual filling demand of Jinchuan as the background，the transport parameters optimized by response surface were as follows：pipe diameter 220 mm，flow rate 142.4 m3 /h，and concentration 73.2%. The research results are of great significance to the selection of the CPB system operating parameters.