18 Seventeenth Avenue is a historic house located at the address of the same name in Sea Cliff, Nassau County, New York.
It was built in about 1890 by Combs & Pearsall, and is a two-story, clapboard sided, Queen Anne style residence with a cross-gabled roof. It features a three-story square tower with a pyramidal roof with overhanging eaves supported by decorative scroll sawn brackets.
It was listed on the National Register of Historic Places on February 18, 1988. It was included in a study covering the Sea Cliff Summer Resort area as a "Thematic Group".