Two-dimensional layered materials have emerged prominently in the past decade, largely being investigated fundamentally and practically. Their unique layered structure and atomic-scale thickness make them attractive with exclusive electrical and optical properties compared to their bulk counterparts. Molybdenum disulfide (MoS 2) is the most widely studied material in the family of transition metal dichalcogenides. The direct and variable bandgap, high carrier mobility, thermal and chemical stability makes it an attractive choice for next-generation photodetector applications. MoS 2 heterojunction-based photodetectors offer ultrafast charge transfer and broadband photoresponse, adding more functionality beyond their individual counterparts. Enormous efforts have been devoted to adopting a new strategy that can improve photodetector performance in terms of responsivity and response time. This review briefly discusses the photo-induced current mechanism and performance parameters along with some important aspects to realize better device performance. Here, we critically review the current status and progress made towards MoS 2-based photodetectors, followed by a discussion on open challenges and opportunities in their future application.