An observational study was conducted for the first time at the ablation area of Potanin glacier, Tavan Bogd region, in western Mongolia in 2007-2008 in order to understand the meteorological and glaciological features. In the study, annual meteorological data and summer surface ablation data were obtained. It was found that the annual mean temperature was -8.8°C on the glacier, and the surface albedo exhibited altitude dependence. Further, the precipitation measured near the glacier during summer was much larger than that measured at Ulgii. Surface energy balance was calculated by a gradient method; it revealed that shortwave radiation was the dominant heat source of surface ablation, whereas the contribution rate of turbulent heat flux was small. The ablation calculated by an equation constructed using the measured radiation showed fairly good correlations with the observed daily ablation, whereas the degree-day method showed good correlations for cumulative ablation. This study revealed the certain uniqueness of the glacio-climate in this region, and showed the further necessity of analysis on the relation of meteorological conditions and the mass balance of the glacier.