Isaac McLellan (May 21, 1806 – August 20, 1899) was an American poet, journalist, and author from Boston, Massachusetts. He is best known for his nature-themed poetry and prose, particularly works depicting the landscapes and seascapes of New England. His notable collections include 'Songs of the Forest and Ocean' (1845) and 'Voices of Nature' (1852). McLellan contributed regularly to the Boston Courier and other periodicals, and in his later years focused on local historical research. He remains a minor but recognized figure in 19th-century American literature.