The aim of this study was to investigate the effect of mountain living conditions and high altitude hiking activities on glucose tolerance. In study I, we performed an oral glucose tolerance test on nine untrained subjects before and after 3 days of mountain living. In study II, the same measurement was used to determine the effect of high altitude hiking in two distinct geographic environments; participants included 19 professionally trained mountaineers. We found that trained mountaineers displayed significantly better sea-level glucose tolerance than sedentary subjects of a similar age (p < 0.05). This result suggests that mountaineering training could produce a beneficial effect on glucose tolerance. More importantly, in study I we demonstrated that 3 days of high altitude living (altitude approximately 2400 m) was sufficient to improve glucose tolerance. Furthermore, hiking in a relatively flat plateau area (Pamirs highland area, China, altitude approximately 4000 m) generated significantly better improvement in glucose tolerance than hiking in a mountain that contained many rough hills at a similar altitude (Mountain Snow, Taiwan, altitude approximately 3800 m). In conclusion, we found that living at a high altitude for the short term can significantly improve glucose tolerance. Additionally, the improving effect of hiking at high altitudes on glucose tolerance appears to be influenced by the geographic environment. These preliminary results suggest that high altitude living conditions and activities may possibly be developed as potential natural medicines for the prevention and treatment of type II diabetes in the future.