Richelmi grabbed the top spot in Friday's qualifying session from DAMS team-mate Marcus Ericsson by 0.276s on his second run on new tyres to score his first career GP2 pole.
Ericsson, who has started from pole twice this year, was forced to settle for second.
Behind the dominant DAMS cars, Barcelona winner Robin Frijns was best of the rest for Hilmer Motorsport, ahead of Mitch Evans (Arden) and Carlin's Felipe Nasr. Fabio Leimer was sixth quickest for Racing Engineering, over half a second off Richelmi's time.
Adrian Quaife-Hobbs was the top Briton in seventh place for MP Motorsport, ahead of James Calado and Silverstone victor Sam Bird.
Tom Dillmann rounded out of the top 10, ahead of Jolyon Palmer. Silverstone sprint race winner Jon Lancaster will start 16th.