Pearl River is a hamlet and census-designated place in the town of Orangetown, Rockland County, New York, United States.

It is east of Chestnut Ridge, south of Nanuet, west of Blauvelt, New York, and north of Montvale and Old Tappan, New Jersey.

In 1696, Pearl River was part of a larger piece of land known as the Kakiat Patent that was granted to Daniel Honan and Michael Hawdon.

[3] Pearl River was a piece of land made up of woods and swamps originally called Muddy Creek.

A third account is that Julius E. Braunsdorf wanted to enhance the hamlet's business image by renaming it Pearl River.

[3] In any event, there is no body of water near the hamlet called Pearl River; the most significant stream is Muddy Brook.

[4] Braunsdorf invented and manufactured the carbon-arc light bulb in 1873, six years before Thomas Edison's carbonized filament version.

To connect Washington, Central, and Franklin he drew three streets and named them William, John and Henry, after his sons.

During World War II, Lederle was a major supplier of vaccines and blood plasma to the U.S. armed forces.

In 1937, AMF acquired the patent rights to this early machine—The “Sch-Bec-Roy”, which stood for Schmidt (inventor), Beckerle (bowling alley proprietor) and McElroy (blueprint designer).

[6][8] In 1955, Pearl River was the setting for Norby, an NBC situation comedy that aired from January to April of that year and was one of the first regular television series filmed in color.

[9][10] It starred David Wayne as a small-town banker who lived and worked in Pearl River, where the 13 episodes of the series were filmed.

[7][19] Streets and a pond on the campus are named after scientists and inventors: Pearl River is the site of Blue Hill Plaza, an office complex that includes Rockland County's first commercial skyscraper, completed in 1972.

[23] The 2010 Pearl River High School girls' softball team won the New York State Championship.