Abstract: Through exploring changes of rheological properties and strength properties of unclassified tailing paste in Bailing copper-zinc mine under the condition of different paste concentrations and cement sand ratio，the influence of paste concentration and cement sand ratio on the properties of paste were determined.In addition，the primary and secondary relationship between the two factors affecting the paste properties was obtained by range analysis，guiding to determine the reasonable range of the paste ratio.The regression equations between the two factors and the paste performance parameters of were established.The test results show that when the paste concentration is 75%~77%，the cement sand ratio is 0.04~0.12，the effect of paste concentration on the rheological properties of paste is greater than that of cement sand ratio，but cement sand ratio is the main factors affecting the strength of paste.According to the actual requirements in Bailing copper-zinc mine and the indoor test results，combining the regression relationship between the concentration as well as cement sand ratio and paste parameters，the optimum paste concentration is recommend to be 77% and the cement sand ratio 0.05 for this mine，which can meet the liquidity requirements and the strength requirements for Bailing copper-zinc mine，providing the safe and reliable technical support for the exploitation of this shallow buried ore body below the highway.

Key words: Under-Three-Objects ore body, Unclassified tailing, Paste, Rheological properties, Strength properties