Lozen Mountain (, Lozenska planina) is a small mountain in Bulgaria. It is at the westernmost end of the Sredna Gora range. To the west, it is separated by the Pancharevo Gorge from the Vitosha and Plana mountains. To the north, its foothills descend into the Sofia Valley. The mountain extends for in an east-west direction, while its width varies between and . Its highest point is Popov Dyal, . It is named after the village of Lozen.