The former Charlton and West Ham boss has ended his five-year sabbatical from the game in order to work alongside Rene Meulensteen at Craven Cottage
Curbishley has concentrated on TV punditry and media work for the last five years since resigning as manager of West Ham in September 2008, despite being linked with a host of other vacancies.
But Fulham have confirmed the 56-year-old will now work with new head coach Rene Meulensteen and chief executive Alistair Mackintosh to try and keep the club in the Premier League.
"I'm very happy that Alan has joined us as I know his expertise will be invaluable as we enter the remaining months of the season," Meulensteen told the club's official website.
"Following Martin [Jol's] departure I discussed with both Alistair Mackintosh and the Chairman the challenges we face, and I was delighted that they supported the idea of additional support within the coaching team.
"Alan has a proven track record in the industry and understands full well what it takes to succeed.
"I look forward to sharing ideas and listening to advice, to ensure Fulham Football Club remains where it belongs: in the Premier League."