Updated project metadata. Chromodomain Helicase DNA-binding Domain 2 (CHD2), as a chromatin remodeling factor, was shown to be involved in the regulation of gene expression in embryonic development, neurodevelopment and myelopoiesis. However, its role in male germ cell development has not been elucidated. Here, we confirmed that CHD2 is abundantly expressed throughout the male germ cells with the highest expression in the spermatocytes of meiosis I. By constructing a heterozygous gene knockout mouse model of Chd2 (Chd2+/-), we demonstrated that CHD2 haploinsufficiency resulted in testicular developmental delay and increased rate of abnormal sperm in mice. DNA damage repair, synapsis and cell proliferation during spermatogenesis are impaired in Chd2+/- mice. In vitro experiments in C18-4 and GC-1 spg cells showed that CHD2 knockdown inhibits spermatogonial self-renewal. Mechanically, CHD2 maintained the enrichment of H3K4me3 in Ccnb1 and Ccnd2 promoter consequently promoting the transcription of Ccnb1 and Ccnd2. In addition, by interacting with cleavage stimulation factor CSTF3, CHD2 binds Oct4, Plzf mRNA and upregulates the expression of OCT4 and PLZF by improving mRNA stability. This is the first time to reveal the role and mechanism of CHD2 in maintaining spermatogonial self-renewal by promoting chromatin activity and mRNA stability in spermatogenesis.