The invention discloses a power distribution network comprehensive evaluation method taking a line as a unit, belongs to the technical field of power distribution networks, and relates to a power distribution network line operation evaluation method based on combined weighting, which is an evaluation method taking advantages of a subjective weighting method and an objective weighting method into consideration and combining operation characteristics of a power distribution network. The method includes: selecting an entropy method and a Delphi method to carry out combination weighting; screeningindexes related to power distribution network line operation by utilizing a fishbone diagram analysis method, and establishing a multi-level index structure system; cleaning the collected data through the big data technology, and improving the data quality; calculating the score value of each index in combination with an improved normal distribution method, enabling each evaluation object to havea better distinction degree, and performing weighted calculation on the comprehensive score of the power distribution network line; and finally, carrying out k-means clustering processing on the comprehensive score of the line, and searching for a weak line in operation.