To ascertain role of the fanconi anemia complementation group G (FANCG) gene in prostate cancer (PCa) and the suitability of the FANCG gene as a prognostic biomarker for PCa.We assessed the expression of FANCG using an analysis of publicly available data sets and cell lines. Physiological functioning of the cells was evaluated through MTT assays and migration assays. Co-expressed genes and enrichment analysis were conducted to probe the biological significance of FANCG in PCa. Quantitative real-time polymerase chain reaction (qPCR) was utilized to detect the expression levels of hub genes (MCM7, MCM5, POLD1, POLA2, LIG1) associated with FANCG.We observed a significant upregulation of FANCG expression in PCa patients and cell lines. Furthermore, immunohistochemical analysis demonstrated markedly higher FANCG protein expression in PCa tissues compared to non-cancerous PCa tissues. Downregulation of FANCG significantly inhibited cell proliferation and migration potential. Evaluation of FANCG-related hub genes (MCM7, MCM5, POLD1, POLA2, and LIG1) revealed their close association with cell cycle-related signaling pathways. Upregulation of FANCG mRNA expression in PCa tissues significantly correlated with high serum PSA levels, advanced pathological stage, high Gleason score, shorter overall survival time, and shorter disease-free survival time.This study suggests that FANCG likely plays a pivotal role in PCa progression. In addition, increased FANCG expression may serve as an indicator of poor disease-free survival and an adverse prognosis for PCa patients.© 2025. The Author(s).