Photothermal therapy (PTT) is a treatment combining laser irradiation and a photothermal transduction agent (PTA) to generate hyperthermia, which is used to efficiently and effectively treat cancer and prevent bacteria-induced infectious diseases. MoS₂, an increasingly used two-dimensional transition metal dichalcogenide, which shows high absorbance in the near infrared (NIR) laser region, has been extensively utilized as a novel PTA in biomedical applications. The use of MoS₂ as an advanced photoabsorbing agent has introduced a more efficient cancer therapy and improved antibacterial efficacy. In this review, we firstly summarize the recent advances in the MoS₂-based platform for PTT in cancer and bacteria-induced infectious diseases treatments. We then discuss that the combination of MoS₂-based PTT and other biomedical methods along with multimodality imaging, such as chemotherapy, photodynamic therapy (PDT) and immunotherapy, might be a promising strategy for cancer treatment. Furthermore, a new concept is proposed wherein MoS₂-based PTT and combined therapies based on this could be more effective for the treatment of various bacteria-induced infectious diseases. Finally, research progress, challenges, and perspectives for the future development of this MoS₂-based platform in cancer and bacteria-induced infectious disease treatments are discussed and concluded. Collectively, we think that MoS₂-based PTT with high therapeutic efficacy and minimal side-effects could be potentially applied in clinical settings to improve cancer and infectious disease treatments.