The 2009 Isle of Man TT Festival was held between Saturday 30 May and Friday 12 June on the 37.733-mile (60.725 km) Mountain Course. The 2009 TT races again include a second 600 cc Supersport Junior TT race and the Lightweight TT and Ultra-Lightweight TT races held on the 4.25-mile (6.84 km) Billown Circuit in the Isle of Man. A new event for the 2009 Isle of Man TT races was the one-lap TTXGP for racing motorcycles "to be powered without the use of carbon based fuels and have zero toxic/noxious emissions."

The Isle of Man TT or Tourist Trophy races are an annual motorcycle racing event run on the Isle of Man in May and June of most years since its inaugural race in 1907. The event begins on the UK Spring Bank Holiday at the end of May and runs for thirteen days. It is often called one of the most dangerous racing events in the world as many competitors have died.