475 Background: DNA polymerases family (DNA pols) has a lengthy reported significant influence on the initiation, development, and progress of cancer. However, the pan-cancer value of whole family members was poorly done. Our study intends to demonstrate the expression pattern and clinical cancer value of DNA pols members as prognostic biomarkers and a therapeutic target of pan-cancer. Methods: Comprehensive bioinformatics analyses were done using data from TCGA and CCLE. MultiCox regression was done to select tumor prognosis-related members. Nomogram was constructed to predict the overall survival (OS) across cancer patients. Transcription factor, GO, IPA, and GSEA enrichments were done to explore regulatory mechanisms and functions. Results: A total of 22 DNA pols were identified to have a potential to diagnostic value, and 10 DNA pols have a pan-cancer prognostic value under various stages, and cancer type, among which overexpression of 6 DNA-pols (POLA2, POLD1, POLD2, POLE2, POLE4, and POLQ) was found to be significantly related to worse outcomes regarding OS, while 4 DNA-pols (POLH, POLL, POLN, and REV1) significantly related to better outcomes. A 5-DNA pols based risk score (POLQ, POLD2, POLL, POLH, and REV1) was generated by MultiCox regression with a nomogram validated an accurate predictive efficacy. MYB Proto-Oncogene Like 2 (MYBL2) was identified as transcription factors of prognostic DNA pols in pan-cancer, and IPA mimic experiment reveals inhibiting MYBL2 could be a drug target to recover and balance the dysregulated expression pattern of DNA pols in pan-cancer. GO, IPA, and GSEA enrichments revealed functions and pathways altered by DNA pols in cancer, and the results were supported by pan-cancer cell sequencing data. Conclusions: DNA pols have a pan-cancer clinical value and can work as potential prognostic biomarkers. Furthermore, MYBL2 could be a drug target for pan-cancer.