The present study illustrates an integrated approach of geospatial technologies, i.e., remote sensing and GIS for assessment of land use/cover dynamics of a district of the Uttarakhand State viz., the Dehradun. Landsat satellite imageries of three different years, i.e., Landsat Thematic Mapper (TM) of 1994, 1999 and 2016 were acquired by USGS Earth Explorer and quantified the land use/cover changes in district Dehradun for a period of more than two decades. Supervised Classification methodology has been employed using Maximum Likelihood Technique in ERDAS 9.3. The images of the study area were categorized into six different land us/land cover classes, viz., vegetation area (in 61.47% area), agricultural land (17.61%), built-up area (6.82%), barren area (5.91%), sediment area (5.67%) and area under water body (2.53%). The results indicate that during the last twenty two years (1994-2016) the vegetation area, built-up area, barren land and sediment area have been increased about 163.67 km², 110.78 km², 83.69 km² and 78.55 km², respectively, while the agricultural land and water body have been decreased about 366.78 km² and 67.91 km², respectively. The approach adopted in this study has clearly demonstrated the potential of remote sensing and GIS techniques in measuring the change pattern of land use/cover.