Published Wednesday, 16 November 2011
O'Sullivan has been in charge of the Eagles for two years and led them at the recent World Cup, guiding them to victory over Russia and a gritty display in defeat to Ireland on 11 September.
He made the move to the USA in 2009, following a six-year spell in charge of Ireland that yielded three Triple Crowns between 2002 and 2008.
But the ex-Connacht coach has decided to pursue opportunities closer to home.
"On behalf of USA Rugby, I'd like to thank Eddie for his time here and I think the Eagles' performance at the Rugby World Cup speaks volumes about him and the way he prepared the team," USA Rugby chief executive and former England scrum-half Nigel Melville said in a statement.
"Moving forward, we'll seek applications for the men's national team head coaching job and are looking forward to choosing the person who will continue to move both the Eagles and American rugby forward."