The Dutchman was dismissed by referee Craig Thomson after bringing down Peter Pawlett on the edge of the box during the 2-1 defeat at Pittodrie on Tuesday, one of several decisions made by the official which left the Hoops manager unhappy.
Speaking at the club's Lennoxtown training complex, Lennon said: "We are appealing because we think it is worthy of an appeal.
"My mind hasn't changed. I think Pawlett was going wider and I think Efe (Ambrose) could have got across to cover.
"We will see what the outcome will be.
"You just never know with these things. It is not like we are wasting anybody's time on it, we feel we have a decent case."