Longfellow Square is a public square in Portland, Maine, United States. Named for the poet Henry Wadsworth Longfellow, it is one of the three main squares on the city's Congress Street — the others being Congress Square and Monument Square, both located a short distance to the northeast. A monument to Wadsworth, erected in 1888, stands in the center of the square, with the seated subject looking east.

The square is bounded by Congress Street to the north and State Street (which intersects Congress Street) to the west and south. Adjacent to the square is One Longfellow Square, a small performing-arts center.

• Portland Railroad Company

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