The character was played by Ryan Reynolds in the 2009 'X-Men Origins: Wolverine' movie and is expected to return, the Hollywood Reporter said.
Reynolds's participation is yet to be confirmed.
'Deadpool', also known as Wade Wilson, first appeared in the New Mutants #98 comic in 1991 by artist Rob Liefeld and writer Fabian Nicieza.
Fox's commitment to making the superhero movie has been slow moving over the last few years. In 2013, director Tim Miller assured fans that the project was still alive.
Miller will work with Lauren Shuler Donner and Kevin Feige, who are producing 'Deadpool'.