Spanish Lake is an unincorporated community and census-designated place (CDP) in St. Louis County, Missouri, United States.

Much of the area was once the property of James De St. Vrain, a brother of the last Spanish lieutenant governor of Upper Louisiana.

The fort served as one of the most important military posts west of the Mississippi River until the troops were removed to the Jefferson Barracks reservation in 1827.

Farmland was intensely cultivated, and small businesses and industries sprang up around the intersection of Bellefontaine, Parker, and Spanish Pond roads, forming the village's center.

The Catholic parish of St. Aloysius in Spanish Lake was founded by, and for many years served as, a mission of Baden, located in the northern portion of St. Louis.

African-Americans fleeing the failed Pruitt-Igoe public housing high rises in the city moved into the apartments via the Section 8 voucher system which immediately struck racial tensions in the area, particularly in local schools.

The 1990s saw a mass exodus of the white population, spurred on by blockbusting, a practice some U.S. real estate agents use to encourage white property owners to sell their houses quickly at a loss, implying the African-Americans moving into their neighborhood will depress their property values.

This era of the city's history is chronicled in the documentary Spanish Lake, although its depiction comes with some disagreement from community stakeholders.