Abstract: Temperature and cement-tailings ratio are the two main factors affecting the mechanical and damage characteristics of cemented tailings backfill. The cemented unclassified tailings backfill samples with different cement-tailings ratios (1∶4, 1∶6, 1∶8, 1∶10 and 1∶12) were prepared by using the unclassified tailings of a metal mine. After curing at different temperatures (20, 35, 40, 45, 50 ℃), the samples were subjected to uniaxial compression, wave velocity and porosity measurement tests to obtain the stress-strain relationship curve and physico-mechanical parameters. Based on the principle of strain equivalence, a damage evolution equation and a damage constitutive model were established to investigate the effects of temperature and cement-tailings ratio on the backfill mechanics and damage characteristics, and the difference between the two effects was explored by grey correlation analysis. The results showed that the compressive strength and elastic modulus of the backfill increased first and then decreased with the increase of temperature, and increased with the increase of cement-tailings ratio, reaching the maximum at a temperature of 45 °C and cement-tailings ratio of 1∶4; the reliability of the model was verified by the comparison between the theoretical value of the constitutive model and the experimentally measured value. The results of the grey correlation analysis indicated that the contribution rate of temperature to wave velocity, porosity, and peak damage was greater than that of the cement-tailings ratio, and the contribution rate to compressive strength and elastic modulus was smaller than that of the cement-tailings ratio. The results can provide a reference for the design of green-filling mining in mines.