The Preuss School (commonly Preuss (IPA:/pɻoːyːs/), Preuss School UCSD, or Preuss Model School) is a coeducational college-preparatory charter day school established in 1999 on the University of California, San Diego (UCSD) campus in La Jolla, California, United States. The school was named in recognition of a gift from the Preuss Family Foundation and is chartered under the San Diego Unified School District.

Preuss uses an intensive college preparatory curriculum to educate low-income students between sixth and twelfth grades, hoping to improve their historical under-representation on the campuses of the University of California. Criteria for admission include that the student's primary guardian lacks a college education and that the student's family qualifies for federal free- or reduced-price lunches under the National School Lunch Act.

The school, which charges no tuition, has received a seven-year accreditation from the Council for Higher Education Accreditation, has been evaluated as a California Distinguished School, has been named by The Center of Educational Reform as one of the top 53 charter schools in America, and in 2007 was listed among the top 10 American high schools by Newsweek and US News and World Report. Preuss sends a high percentage of its graduates to four-year universities.