whole-genome bisulfite sequencing (WGBS) was performed to compare the global DNA methylation changes in the Nile tilapia sex-undifferentiated gonads at 17 dah (days after hatching) from FC (XX Female Control), FT (XX Females after high-temperature treatment during the TSP) and MC (XY Male Control) fish. Integrated analysis of DNA methylome and RNA transcriptome data showed that 5, 123 and 477 DMGs (DMR related genes) exist in FC vs FT, FC vs MC and MC vs FT, respectively. Additionally, many important pathways, including neuroactive ligand-receptor interaction, insulin signaling pathway, and Calcium signaling pathway were identified.