The West Ham midfielder, who joined the club from Manchester United, faces a hearing after using abusive and insulting language on the social networking site
The former Manchester United man, who left Old Trafford for the Championship side in January, was charged on Wednesday over a derogatory reference to a person's sexual orientation.
Morrison responded on Friday, and is set to learn his punishment, having requested a non-personal hearing.
An FA statement read: "West Ham United’s Ravel Morrison has admitted a charge under FA Rule E3 of using abusive and/or insulting words including a reference to a person’s sexual orientation in relation to Twitter comments.
"Morrison has requested a non-personal hearing."
Morrison is yet to make an appearance for West Ham since making the move to the top of the Championship side last month.
The midfielder did however play twice in the League Cup for Manchester United before leaving in January.
Morrison was highly rated by Sir Alex Ferguson, but a series of incidents off the field and problems regarding a new contract for the youngster culminated in his exit.
"The case with Ravel is well documented, I think he’s better out of Manchester to be honest with you," the United manager recently told the club's official website.
"He’s got a great talent, but having to deal with that is very important."