Like most other V8 Supercar drivers, Greg Murphy started out in karts before moving into V8 Supercars. Murphy moved from New Zealand to Australia to race Formula Holden open-wheelers however began to race with Audi Sport Australia while competing in V8 Supercar endurance events with Craig Lowndes and the Holden Racing Team.

In 2001 Murphy moved into the Kmart Racing Team where he stayed until the end of 2004. During this period Murphy won Bathurst a third and fourth time in 2003 and 2004. At the time, his 2003 Bathurst win marked the fastest qualifying lap time ever, with a lap time of 2.06.8594 putting him on pole.

In 2012, Murphy embarks upon his 15th season as a full-time driver in the V8 Supercar Championship Series.