An octagon barn is a barn built in an octagonal shape, see .
As a proper name, Octagon Barn or Octagonal Barn may refer to:
United States San Luis Obispo Octagon Barn, San Luis Obispo, California Kinney Octagon Barn, Burr Oak, Iowa, listed on the U.S. NRHP Secrest Octagon Barn, Downey, Iowa, NRHP Fobes Octagon Barn, Lanesboro, Iowa, NRHP Octagon Barn, Otter Township, Milo, Iowa, NRHP Octagon Barn (Polk Township, Iowa), Octagon Barn, Richland Township, Iowa, NRHP Roberts Octagon Barn, Sharon Center, Iowa, NRHP Grimes Octagon Barn, West Union, Iowa, NRHP Thumb Octagon Barn, Gagetown, Michigan Marsh Octagon Barn, NHRP in Wright County, Minnesota J. F. Roberts Octagonal Barn, Rea, Missouri, NRHP Octagonal Poultry House, Cold Spring, New Jersey, NRHP Lattin-Crandall Octagon Barn, Catherine, New York, NRHP Lunn-Musser Octagon Barn, Garrattsville, New York, NRHP Mexico Octagon Barn, Mexico, New York, NRHP Baker Octagon Barn, Richfield Springs, New York, NRHP Rodman Octagonal Barn, Edgeley, North Dakota, NRHP Gerhardt Octagonal Pig House, Gladstone, North Dakota, NRHP Sylvanus Marriage Octagonal Barn, New Rockford, North Dakota, NRHP James Wimer Octagonal Barn, Lookingglass, Oregon, NRHP Harnsberger Octagonal Barn, Grottoes, Virginia, NRHP Rankin Octagonal Barn, Silverton, West Virginia, NRHP Tim Thering Octagon Barn, Plain, Wisconsin
See also List of octagonal buildings and structures in the United States Octagon Building (disambiguation) Octagon House (disambiguation) Polygonal Barn (disambiguation)