Magnesium is among the lightest structural metals available, with the capacity to replace traditional alloys in mass-saving applications while still providing increased stiffness and strength. The inclusion of reinforcing components into the metallic matrix has a substantial impact on stiffness, specific strength, wear behaviour, damping behaviour, and creep properties when compared to typical engineering materials. Due to their outstanding physical and mechanical characteristics along with low density, magnesium metal matrix composites are viable materials for numerous applications. This study discusses how to choose an appropriate technique and its process parameters for synthesising magnesium-based metal matrix composites (MMCs) and gives an overview of the impacts of various reinforcements in magnesium and its alloys, emphasising their benefits and drawbacks. The essential applications of various magnesium-based MMCs are also critically examined in this article. The impact of reinforcement on the microstructure as well as mechanical characteristics are thoroughly examined.