Lonetree is a census-designated place in Uinta County, Wyoming, United States. The population was 49 at the 2010 census. Lonetree is located at 41°2′9″N 110°9′44″W / 41.03583°N 110.16222°W. According to the United States Census Bureau, the CDP has a total area of 45.6 square miles, of which 45.6 square miles is land and 0.04 square mile is water.