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The snowline altitude at the end of melting season (SLA-EMS) provides a possibility to rapidly obtain a proxy for their equilibrium line altitude (ELA) which in turn is an indicator for the glacier mass balance. SLA-EMS is also an important parameter for the study of the relationships between climate and cryosphere. High Mountain Asia (HMA) hosts the largest glacier and perennial snow cover concentration outside the polar regions, but the spatial and temporal patterns of SLA-EMS are poorly understood. Here we investigate the spatial and temporal variation characteristics of SLA-EMS over the HMA on a grid-by-grid (30 km) basis, by using the cloud-removed MODIS fractional snow cover datasets from 2001 to 2016. The possible linkages between the SLA-EMS, temperature, precipitation and solar radiation changes over the HMA are also investigated. The results are as follows: (1) the proposed MODIS-based grids (30 km) SLA-EMS extracting method is efficient in monitoring the spatiotemporal patterns of the SLA-EMS for a large-scale area. (2) In the HMA, the spatial change of the SLA-EMS (from 3114 to 6907 m) exhibits a large spatial heterogeneity. The SLA-EMS decreases from the high altitude region of Himalayas and inner Tibet to surrounding low mountainous area. (3) The SLA-EMS of HMA generally shows a rising trend in the recent years (2001–2016). In total, 82.35% (26.32% with a significant increase) and 17.65% (0.74% with a significant decrease) of the study area show increasing and decreasing trends in SLA-EMS, respectively. The SLA-EMS significantly increases in east Tien Shan (5.16 m yr−1), west Tien Shan (4.64 m yr−1), Inner Tibet (3.64 m yr−1), south and east Tibet (9.18 m yr−1), east Himalaya (8.52 m yr−1) and Hengduan Shan (7.48 m yr−1). (4) The summer temperature trends to be the dominant climatic factor affecting the variations of SLA-EMS over the HMA. [ABSTRACT FROM AUTHOR]