Town go into the game at the West Riding County FA's Fleet Lane base, in Leeds, as holders and favourites after last season's promotion to the National League Northern Premier, one level higher than their opponents from Division One North.
But Mitchell is making sure that his players remain focused on the task in hand, saying: "We have been favourites in the past and we have been underdogs and I know that you can take nothing for granted.
"It's a cup final and anything can happen so we have to make sure that we do a professional job and focus on what we are doing. It won't be easy and we have to prepare properly.
"Leeds will be up for it and they may see themselves as underdogs so they will want to get one over us. I know a lot about them [Leeds]. They have threats in their team and they will want to finish their season on a high."
The majority of Mitchell's new-look squad didn't feature in Town's last County Cup final appearance, which should make it easy to motivate the young side. Mitchell said: "A cup win will be a big boost for the team.
"At the start of the season we said we wanted to defend the cup and finish in the top eight and we are on target to do that."