The Rodin Carlin driver had scored eight podiums before finally taking his first victory in the series on Saturday in Belgium.
Having lined up third, he held position off the line behind poleman Jehan Daruvala (MP Motorsport) and Van Amersfoort Racing driver Richard Verschoor.
Though Daruvala initially took control, he was forced to retire on lap two after his headrest flew off, handing the lead to Verschoor.
Despite the Dutchman building a two-second lead, Fittipaldi fought back, taking the lead into Les Combes on lap 16 with the help of DRS.
He immediately built over a second lead to ensure Verschoor would be unable to replicate the move, crossing the line for his maiden victory, with championship contender Theo Pourchaire in third for ART.
The start of the race was delayed by 35 minutes after the earlier Formula 1 sprint shootout was pushed back due to rain.
Joshua Mason, making his F2 debut for PHM Racing by Charouz this weekend, stalled on the grid, prompting a 10-second penalty for a start procedure infringement.
Source: Autosport