Both were activated before the team's game Friday night against the Vancouver Canucks.
Galiardi has missed nine games since injuring his ankle Oct. 28 at Calgary. He has one goal and five assists for Colorado this season.
Liles missed five games after injuring his shoulder Nov. 6 against Chicago. He has two goals and three assists for the Avalanche this season.
The Avalanche also reassigned forward Chris Durno to the Lake Erie Monsters of the American Hockey League on Friday and placed forward Matt Hendricks on the injured reserve list retroactive to Nov. 14 with a groin injury.