Old Speck Mountain, also known as Old Speckle Mountain, is a mountain located in Oxford County, Maine, United States. The mountain, the fourth-highest in the state, is the northeasternmost and highest of the Mahoosuc Range, the northeasternmost part of the White Mountains. Old Speck is flanked to the southwest by Mahoosuc Arm, and faces Baldpate Mountain to the northeast across Grafton Notch.