The Northern Ireland international winger picked up a knock in Saturday’s 3-0 home Premiership win over Ross County.
The Dons will also be without defender Clark Robertson (thigh) and skipper Russell Anderson (knee).
Livingston, who are fifth in the Championship table with seven points from six matches, beat Queen of the South 1-0 after extra-time in the second round.
However, they will have to bounce back from a 1-0 home defeat to Raith Rovers on Saturday if they are to shock the cup holders.
Aberdeen boss Derek McInnes believes the memory of winning the League Cup last season will act as motivation for his players this campaign.
He said: “We saw how important it was to bring that silverware back. We saw the benefits it brought to the city.
“It whets the appetite for everybody, the supporters and players alike. We want to experience days like that more often and the cups do bring that opportunity for every club, Livingston included, and I am sure every one of the Premiership clubs at the start of the campaign will feel that it could be them.
“Livingston won’t be fazed. For us to get into the next round, we are going to have to deal with that challenge, but obviously the motivation for us, after last season, is there.
“It is easy to visualise after last season’s cup final and taking 43,000 fans to the final. Our players will want to experience that again.”