The invention provides a line loss abnormality diagnosis method and a device based on an electric quantity curve characteristic model. The method is applied to the technical field of electric power. The method comprises the following steps of: obtaining first source data from a first system; obtaining the first source data from the first system; processing the first source data according to a preset rule in a second system to obtain second source data. A Pearson correlation coefficient algorithm is used to perform a first line loss anomaly diagnosis analysis on the second source data, and a clustering algorithm and a decision analysis algorithm are used to perform a second line loss anomaly diagnosis analysis on the second source data. The method and device for analyzing line loss abnormality based on characteristic parameter model of electric quantity curve provided by the invention adopt twice line loss abnormality analysis, the calculation speed is fast, the data acquisition is convenient, and the reliability of the analysis result is high.