The Buick GSX is a high-performance variant of the Buick Gran Sport (GS), produced by the American manufacturer Buick in the early 1970s. The GSX was introduced as a limited-production muscle car designed to compete within the high-performance segment of its era.

The GSX was typically based on the Buick Skylark platform and powered by large-displacement V8 engines, including high-output variants designed for strong straight-line acceleration. It featured performance upgrades such as enhanced suspension components, sport-oriented styling details, and distinctive exterior graphics.

Produced in relatively small numbers, the Buick GSX has become a sought-after collector vehicle. It is associated with the peak of the American muscle car era, representing Buick’s contribution to performance-focused automotive engineering during the late 1960s and early 1970s.