It had launched a legal challenge against the project that was dismissed in the Ontario Superior Court in late July.
The court decision stated the city acted "in good faith" when it awarded the $300-million contract to the Ottawa Sports and Entertainment Group in June 2010.
But in a statement on Wednesday, the group said a call to action from members of its mailing list inspired it to appeal.
"Friends of Lansdowne will argue that the Superior Court allowed Ottawa's city council far too much latitude in regard to restrictions set out in provincial law concerning competitive procurement, the use of tax dollars to assist commercial entities and the requirement that it put the public interest first," the coalition added in a statement.
The case will be heard in late 2011 or early 2012, the group added.
FOL's court case has delayed the construction and completion of Lansdowne until at least 2015, the city has said.
Renovation plans call for changing the old football stadium, constructing a parking garage and adding retail and residential elements to the Glebe facility.
Separately, there will be a separate city council meeting to discuss Lansdowne today.