Abstract: Working characteristics of filling slurry,including fluidity,stability and plasticity,are important factors affecting the pipeline transportation of filling slurry. In order to quantitative evaluate and classify the working characteristics of filling slurry,based on the summary of theoretical analysis methods,the mass ratio of waste rock to bar grinding sand,cement sand ratio and slurry mass concentration were selected as three influencing factors of working characteristics,and slump,diffusivity,consistency,stratification,bleeding rate,yield stress and viscosity coefficient were selected as seven evaluation indexes,48 groups of slurry working characteristics were tested with coarse aggregate from a mine in Gansu Province. The correlation between the experimental work characteristics was analyzed by using the Pearson theory,the result shows there is a significant correlation,primary component analysis is needed for evaluation indicators. In order to eliminate the repetitive information between evaluation indicators,primary component analysis(PCA) was used to reduce dimension of evaluation indicators,and two unrelated indicators which simplify the characterization of working characteristic parameters were obtained and qualitative evaluation of working characteristics. Two new indicators were converted into one quantitative evaluation index by comprehensive evaluation function,and the qualitative analysis results of the evaluation indicators are optimized. Based on PCA and distance discriminant analysis(DDA),a PCA-DDA model for classification and discrimination of working characteristics of coarse aggregate filling slurry was established. The results of model prediction show that under 11 different training and testing groups,the error rate of distance discrimination is less than 10%,and the error probability of model is less than 7%,satisfiing the accuracy requirement.