Infection-related cancer comprises one-sixth of the global cancer burden. Oncoviruses can directly or indirectly contribute to tumorigenesis. Ubiquitination is a dynamic and reversible posttranslational modification that participates in almost all cellular processes. Hijacking of the ubiquitin system by viruses continues to emerge as a central theme around the viral life cycle. Deubiquitinating enzymes (DUBs) maintain ubiquitin homeostasis by removing ubiquitin modifications from target proteins, thereby altering protein function, stability, and signaling pathways, as well as acting as key mediators between the virus and its host. In this review, we focus on the multiple functions of DUBs in RIG-I-like receptors (RLRs) and stimulator of interferon genes (STING)-mediated antiviral signaling pathways, oncoviruses regulation of NF-κB activation, oncoviral life cycle, and the potential of DUB inhibitors as therapeutic strategies.