Alessandro Pier Guidi was born on 18 December 1983 in Tortona, Piedmont. He began racing in karts as a child and made his debut in a single-seater in 2002, competing in Formula Renault Italia with the Birel Formula team. He debuted in GT racing competitions in 2005 for Playteam for which he drove a Ferrari 360 Modena GTC in GT championships in Spain and Italy. Paired with Giambattista Giannoccaro in the Spanish series he won at Jarama, Valencia, Estoril and Barcelona, while in Italy he triumphed at Misano, Magione and Mugello with Toni Vilander. In early 2006 he also won the Mil Milhas Brasil race at Interlagos with Giannoccaro and Vilander.Again with Playteam in that same year, paired with Michael Bartyan, he competed in the International GT Open (winning at Monza, Magny-Cours and Barcelona) and in the Spanish GT (wins at Jarama and Albacete) with the new F430 GTC. During the winter he also took part in four single-seater races in the A1 Grand Prix. In 2007 he drove intermittently in the FIA GT in the GT1 class for Maserati with which in four years he won a race at Zolder and two podiums in the 24 Hours of Spa-Francorchamps. In 2008, he returned to the single-seater taking part in the Formula Superleague in which he took three third places for Galatasaray. Again with Maserati he competed in a number of races in the GT4 class also winning the 6 Hours of Vallelunga in 2010 alongside Andrea Bertolini. In 2011 he returned to the wheel of a Ferrari triumphing in the Barcelona race of the International GT Open in the F430 of Vittoria Competizioni paired with Juan Manuel Lopez. The following year he won the 24 Hours of Spa-Francorchamps in the Pro-Am class in the new 458 Italia GT3 of AF Corse with Louis Machiels, Niek Hommerson and Bertolini, while at the end of the year he emerged victorious in the 6 Hours of Vallelunga with the 458 Italia GT3 of Estamotorsport alongside Alessandro Balzan and Alexander Skryabin. Alessandro's most prestigious win was in 2014 when he was a member of the crew that triumphed at the 24 Hours of Daytona at the wheel of the 458 Italia of Level 5 Motorsports with Townsend Bell, Bill Sweedler, Scott Tucker and Jeff Segal. In the same year he competed in the European Le Mans Series (ELMS) with the 458 Italia GTE of Team Ukraine winning the 4 Hours of Silverstone in the GTC class alongside Andrii Kruglyk and Sergey Chukanov. In 2015 he teamed up in the European Le Mans Series with Alexander Talkanitsa father and son winning the race at Imola. He took the laurels again in the 24 Hours of Spa-Francorchamps in the Pro-Am class at the wheel of the 458 Italia GT3 of AF Corse with Stephane Lemeret, Gianmaria Bruni and Pasin Lathouras. In 2016 he competed in three continents with various Ferrari customer teams and made his debut in the 24 Hours of Le Mans alongside Bruni and James Calado in the 488 GTE of AF Corse.