In this study, numerical simulations of transport phenomena in a differentially side heated lid-driven cavity with power law fluids is reported. Finite volume method with uniform grid is employed to solve the governing equations of mass, momentum, and energy transfer in the cavity. The Oswald-de Waele model is incorporated into the simulations which is a commonly used model for power law fluids. A wide range of non-dimensional parameters like Reynolds Number (100≤Re≤500), Grashof Number (10²≤Gr≤2.5×10⁶), Prandtl Number (0.1≤Pr≤100) and Richardson Number (0.01≤Ri≤10) are investigated. The value of power law index with a variation (0.25≤n≤1) is considered for this study. While the flow field is visualized by presenting streamlines and isotherms, local and area-averaged Nusselt number plots depict the thermal behavior. Results show that the transport phenomenon in a differentially side heated lid-driven cavity is significantly affected by the power law behaviour of the fluid along with variation in the Reynolds, Richardson and Prandtl numbers. The non-Newtonian behaviour of the fluid leads to the formation of vortices and recirculation zones in the cavity, which affects the heat transfer rate in the cavity. These findings have important implications for the design and optimization of industrial processes that involve power law fluids.