Chief executive Alan Hardy told the Oldham's official website: "We sat down with Andy to discuss his situation and the result was the club would be terminating his contract.
"An agreement has been reached on a settlement and the player has left the club with immediate effect."
It is unclear at present whether Liddell will retire or not.
One thing that is for sure is that Liddell scored 50 goals for Wigan in over 200 appearances for the club and is certainly a firm fans favourite from the past.
CLICK HERE FOR THE MESSAGEBOARD