Mammalian meiosis is a cell division process specific to sexual reproduction, whereas a comprehensive proteome related to different meiotic stages has not been systematically investigated. Here, we isolated different types of germ cells from the testes of spermatogenesis-synchronized mice and quantified the corresponding proteomes with high-resolution mass spectrometry. A total of 8,002 proteins were identified in nine types of germ cells, while the protein signatures of spermatogenesis were characterized by the dynamic proteomes. A supervised machine learning package, FuncProFinder, was developed to predict meiosis-essential candidates based on the proteomic dataset. Of the candidates with unannotated functions, four of the ten genes at the top prediction scores, Zcwpw1, Tesmin, 1700102P08Rik and Kctd19, were validated as meiosis-essential genes by knockout mouse models. The proteomic analysis towards spermatogenic cells indeed setups a solid evidence to study the mechanism of mammalian meiosis. The proteome data are available via ProteomeXchange with identifier PXD017284.Up to now, transcriptional gene expression in thousands of germ cells covering various developmental stages of spermatogenesis were quantified at single cell level 9-15 , resulting in very detail transcriptome landscape throughout spermatogenesis, yet few studies explored the data for further functional excavating. As gene expression at protein level are downstream of transcription, proteomic abundance change of genes could be more directly associated with phenotype or functional change. Importantly, multiple studies clarified a poor correlation between mRNA and protein abundance in testes 16,17 , therefore, a global proteomic profiling of gene expression in spermatogenesis is of great meaningful to unravel functional molecules of meiosis. However, the report regarding systematic profiling of proteomics during meiosis was limited. Only one type of meiotic cells-pachytene spermatocytes was quantified in previous proteomics studies 7, 17 , leaving protein expression remained unknown in most of the stages in meiosis. Therefore, in contrast to meiotic dependence of transcriptomes in details, quantified profiling of meiotic proteome has remained a large room to be improved, as well as digging for functional molecules from a big omics dataset.In this work, to understand the molecular basis of mouse meiosis and predict meiosis-essential proteins, 7 consecutive types of meiotic cells plus pre-meiotic spermatogonia and post-meiotic round spermatids were isolated and the proteins in each cell-type were identified and quantified by high-resolution mass spectrometry with a label-free mode. The meiosisdependent signatures were characterized by protein abundance changes. Furthermore, a supervised ensemble machine learning package, FuncProFinder, was developed to predict the meiosis-essential proteins. The meiosis-related phenotypes for the five proteins at the top scores of the prediction, Pdha2, Zcwpw1, Tesmin, Kctd19 and 1700102P08Rik were verified by knoc...