Natural and human induced changes to the earth surface are the main cause of thermal heterogeneity of earth’s surface. Remotely sensed thermal infrared (TIR) data for determining Land Surface Temperature (LST) allows continuous global coverage that enables the assessment and quantification of these variations. The current study was designed with the goal of determining UHI in the metropolitan Lahore. i.e., the provincial capital of Punjab, Pakistan. Developing a broad-ranged, multidimensional, economically viable long-term policy to address difficulties originating from changes in the microclimate of urban areas necessitates a thorough understanding of spatiotemporal variations in LST of the region of concern. Therefore, from 2000-2020, the LST of Lahore was determined using Landsat 5 and Landsat 8 OLI images. NDVI, NDBI, Built-up Index (BUI) and NDWI results indicated the definite increase in spatial coverage of LST in Lahore and LULC identified the increasing trend in built-up area. The role of climatological variables and increasing urban population and population density on the LST and UHI of Lahore were also investigated. This facilitated the understanding of complicated interactions of LST with various physical, climatological and social factors of the city.