Hazard agrees terms with Chelsea
The versatile 21-year-old, who has been with French club Lille since 2005, will join up with Chelsea in July.
"Chelsea Football Club is delighted to announce we have agreed terms with Lille for the transfer of Eden Hazard," the European champions said on their website.
A target for many of Europe's top clubs, Hazard said he was delighted to have joined the London club as they begin a rebuilding process following last season's disappointing sixth placed finish in the Premier League.
"I'm delighted to finally arrive here, it's a wonderful club and I can't wait to get started," he said.
Hazard, named best Ligue 1 player in the past two seasons, led Lille to the French title in 2011 and scored 20 goals in the last campaign, including a hat-trick in the final game of the season to secure a third-placed finish for the club.
Hazard is the fourth Belgian to join Chelsea, following the arrivals of Thibaut Courtois, Romelu Lukaku and Kevin De Bruyne.