While Bulgaria has oligotrophic lakes in mountain zones with Pinus mugus shrubs associated with mountains with Fagus forests, northern Chilean Patagonia has numerous pristine lakes associated with Nothofagus forests. The present study consists of an optical properties description of mountain lakes from Bulgaria with Chilean mountain lakes (Huerquehue and Alerce Andino National Parks) with Nothofagus forest, in visible, close, and medium infrared wavelengths. The results revealed that Bulgarian lakes have different optical properties than Chilean lakes, in spite of the oligotrophy associated with surrounding vegetation and geological characteristics of both groups of studied sites.