The Toro Rosso STR3 was used by Scuderia Toro Rosso in the 2008 Formula One season and designed by Adrian Newey, the Red Bull Racing designer.

Sebastian Vettel, who (since joining Scuderia Toro Rosso) makes it a habit to give his racing cars names, named his STR 3 'Julie'. It was first tested by Red Bull junior driver, Brendon Hartley in Italy on 2 April and publicly launched on 16 April 2008 at the Circuit de Catalunya, where it was driven by Sébastien Bourdais.

Toro Rosso had started the 2008 season with an updated B specification version of their 2007 STR2 car, originally stating that the STR3 would make its début at the fourth or fifth round.

The car was first raced at the 6th round of the season, the Monaco Grand Prix, driven by Sébastien Bourdais and Sebastian Vettel. It was driven by Vettel to victory in the Italian Grand Prix, the team's only and Vettel's first victory.