The Super Proton Synchrotron (SPS) is a particle accelerator at CERN. Originally specified as a 300 GeV machine, the SPS was actually built to be capable of 400GeV, an operating voltage it achieved on the official commisioning date of 17 June 1976. However, by that time this voltage had been exceeded by Fermilab, who reached 500GeV on May 14th of that year.

The SPS was designed by a team led by CERN director-general of what was then known as Laboratory II, Sir John Adams.

The SPS has been used to accelerate antiprotons, for a proton-antiproton collider, electrons and positrons (for use as the injector for CERN's LEP electron-positron collider) and heavy ions.

The SPS is now to be used as the final pre-injector for high-intensity proton beams for CERN's Large Hadron Collider, scheduled to begin operation in 2006, accelerating protons from 26GeV to 450GeV. The SPS will also be used to produce a neutrino stream to be detected at the Italian Gran Sasso laboratory, 730 km from CERN.