The 2015 GP3 Series was the sixth season of the third-tier of Formula One feeder championship and also sixth season under the moniker of GP3 Series, a motor racing feeder series that was run in support of the 2015 FIA Formula One World Championship and sister series GP2. Thirty-one drivers represented eight teams over the course of the season's nine rounds, starting in Spain on 9 May and ending in Abu Dhabi on 29 November. It was the final season for the Dallara GP3/13-AER P57 V6 chassis and engine package that debuted in 2013. A new Dallara-built chassis was introduced for 2016 along with a Mecachrome normally-aspirated V6 engine.
French driver Esteban Ocon (ART Grand Prix) finished the campaign as the drivers' champion after a season-long battle with Trident driver Luca Ghiotto. Despite winning only one race in 2015 – the first race in Barcelona – Ocon took fourteen podium finishes, including a run of nine successive runner-up placings over the mid-course of the season.[1] Ocon ultimately finished eight points clear of Ghiotto, who won a season-high five races. Another five-time winner, Marvin Kirchhöfer, completed the championship top three, some fifty-three points behind team-mate Ocon. The performances of Ocon and Kirchhöfer were more than enough for ART Grand Prix to regain the teams' championship title they had missed out on for the first time in 2014. Five other drivers took race victories during the 2015 season; Arden International pairing Emil Bernstorff and Kevin Ceccon each took two victories, while Jimmy Eriksson, Álex Palou and Óscar Tunjo each took sprint race victories, which were held with partially-reversed grids – an inversion of the top eight finishers in the previous day's feature race.