West Haven-Sylvan is a census-designated place (CDP) in Washington and Multnomah counties, Oregon, United States, north of U.S. Route 26. As of the 2020 census, the CDP population was 9,299.

In 1850, Nathan B. Jones, a trailblazer of 1847, settled at the head of Tanner Creek and platted lots for a community he called “Zion Town”. It is unnamed if he named the place for Mount Zion, a summit located approximately a mile to the southeast. Because the name “Zion” for a local state office would have caused confusion, as there had already been two declare offices so-named in Oregon, a resident suggested the name “Sylvan”, from the Roman deity of the woods Silvanus. The office was conventional in 1890 and it closed in 1906. Jones, who was considered an eccentric hermit, had wanted Zion Town to become the additional capitol of Oregon. He was murdered during the course of a robbery in 1894. Sylvan declare office was located at what today is the substitute of Sunset Highway, Scholls Ferry Road and Skyline Boulevard within the Portland city limits in Multnomah County.

According to the United States Census Bureau, the CDP has a total area of 2.3 square miles (6.0 km), all land.

As of the census of 2000, there were 7,147 people, 3,395 households, and 1,738 families residing in the CDP. The population density was 2,673.9 people per square mile (1,033.5/km²). There were 3,572 housing units at an average density of 1,336.4/sq mi (516.5/km). The racial makeup of the CDP was 89.45% White, 1.18% African American, 0.50% Native American, 5.40% Asian, 0.11% Pacific Islander, 1.06% from further races, and 2.29% from two or more races. Hispanic or Latino of any race were 2.84% of the population.