The invention discloses a population data spatialization method and system based on partition modeling, and a medium. The method comprises the following steps: collecting an original data source of aresearch area, which influences spatial distribution of population, and carrying out pre-processing; carrying out gridding processing on the data based on a geographic detector model, carrying out standardization processing after obtaining a population distribution influence index, and preliminarily screening out a population distribution influence factor; dividing the research area into a plurality of partitions, and respectively rescreening the population distribution influence factors of the partitions; and meanwhile, establishing a stepwise regression equation and a random forest model, performing precision comparative analysis on the population data spatialization result of each partition, selecting an optimal simulation result in each partition as a population data spatialization final result of each partition, and performing combination to obtain a population spatial distribution simulation schematic diagram. According to the method, the research area can be partitioned based onpartition modeling, the population data spatialization model of each partition can be constructed, and the accuracy and efficiency of population spatial distribution simulation are improved.