Glacial lakes in the central Himalayas are expanding at an unprecedented rate due to the rapid melting and thinning of glaciers. The continuous growth of glacial lakes increases the availability of freshwater for the downstream communities and escalates the risk of future Glacial Lake Outburst Floods (GLOFs) in the upper Ganga basin. In the present study, glacial lake inventories for the years 1990, 2000, 2010, and 2020 were prepared at the sub-basin level to understand the evolution of glacial lakes in the upper Ganga basin at the micro-regional scale. We found that, between 1990 and 2020, the total number of glacial lakes increased by 564 (22.08%) and the total area increased by 40.71 km2 (23.93%). We found that glacial lakes were present in the 28 sub-basins of the upper Ganga basin. Among different types of glacial lakes, end-moraine-dammed (M(e)) (n: 2413 and a: 178.89 km2) had the highest proportion both in terms of number and area of different types of glacial lakes. We, furthermore, estimated the volume and mean depth of glacial lakes using (Huggel et al. 2002) empirical equations. The total estimated volume of glacial lakes was 5.548 km3 (2020), and the average estimated mean depth was 8.26 m (2020). Between 1990 and 2020, the estimated volume of glacial lakes increased by 1.46 km3 and the average estimated mean depth decreased by −0.20 m.