QSA

QSA may refer to:


 * Qt Script for Applications, a scripting engine
 * Quaker Social Action
 * Qualified Security Assessor, a certification by the Payment Card Industry (PCI) Security Standards Council
 * Quantification Settlement Agreement, a water distribution plan
 * Queens of the Stone Age, a band
 * Queen's Scout Award
 * Queen's South Africa Medal for service in the Boer War
 * Queensland State Archives
 * Queer-straight alliance