The invention discloses a project attribute-based distribution network input-output correlation analyzing method. The project attribute-based distribution network input-output correlation analyzing method comprises the following steps: constructing a distribution network input and output evaluating index system; according to physical characteristics of a distribution network, analyzing correlationbetween input indexes and output indexes of the distribution network based on project attributes to obtain a correlation coefficient matrix; with the minimum sum of deviations between actual values and predicted values of the output indexes as an objective and the maximum and minimum increasing rates of a unit investment output index as constraints, establishing a mathematical model of an input-output functional relationship; solving the mathematical model to obtain a corresponding functional relationship between the input indexes and the output indexes of the distribution network. By the project attribute-based distribution network input-output correlation analyzing method, during distribution network input-output correlation analysis, whether the input indexes and the output indexes arerelevant or not is analyzed, a specific function relationship between input and output is also given, and quantification between the investment amount and increase in the output indexes is achieved.