The invention discloses a target modeling method for a distribution network dispatching system based on global optimization. The target modeling method is mainly applied to estimation and optimization of the distribution network dispatching system. The target modeling method includes the steps of building a global optimization target model according to indexes needing to be calculated for the estimation and optimization of the distribution network dispatching system and the existing relations between the indexes, calculating the weight of each index of a global optimization target, calculating an index value of each global optimization index on the basis of system operation data and history data of the distribution network dispatching system, dividing the indexes into ultra-large indexes, ultra-small indexes and fixed indexes according to the condition of the optimal values of the indexes, grading each index value, and calculating the total score of the global optimization target. Through the adoption of the target modeling method for the distribution network dispatching system based on the global optimization, integration modeling is carried out on the indexes with different calculated values and variation trends, a global optimization general target is obtained, and therefore the target modeling method facilitates integration optimization analysis of the multiple indexes of the distribution network dispatching system.