Abstract: The invention pertains to the field of genomics and bioinformatics, and relates to a cfDNA classification method, apparatus and application. Specifically, the present invention relates to a cfDNA classification method, comprising: calculating a copy number variation data of cfDNA in a target sample; calculating a similarity degree between the target cfDNA copy number variation data and the cfDNA copy number variation data of each category label; and determining the category to which the target cfDNA belongs according to the similarity degree by using a classifier model. The invention can realize the diagnosis of up to 3 types of urogenital system tumors at one time, and has high sensitivity and specificity. In particular, in the diagnosis and dynamic monitoring of urothelial cancer, the sensitivity and specificity are higher than those of the current clinical detection methods.