United beat Aston Villa 4-1 at home on Saturday, but their previous two Premier League matches at Old Trafford saw them lose 3-0 to both Liverpool and Manchester City.
That has led to runaway German champions and reigning European champions Bayern being installed as 4/9 shots to win the game by Sky Bet with United quoted at 11/2 to triumph on their own turf.
However, Moyes is expecting a big performance from his side and he believes they are capable of producing a shock result.
He said: "We are going into the game knowing that on our day we are as good a side as any.
"We have to show it more often than we have done but I have great belief in the players. I have said that from day one and it hasn't changed.
"I get the feeling they (the players) all want to play. I can tell by their training and their attitude that they are saying 'this is a big game' and they all want to play in the big games. That's what I think that over the years the players here have wanted to do."
Moyes will be locking horns with Bayern coach Pep Guardiola for the first time and the under-pressure Scot has confidently predicted it will be the first of many meetings with the Spaniard.
"I am really looking forward to coming up against Pep Guardiola," he said. "It is the first time I have done but I have no doubt I will be doing it many times in the future."
Guardiola has already guided Bayern to the Bundesliga title with seven matches to spare in his first season in charge - in contrast to Moyes' troubled first campaign at Old Trafford - but Moyes reckons the former Barcelona boss has had an advantage over him as he took a 12-month sabbatical before taking over.
"He has had a year to get ready for the Bayern job," Moyes said.
"He has done incredibly well with them, he has taken over the European champions but his record with them has been very good."
United right-back Rafael is a doubt for the game with a thigh strain, while left-back Patrice Evra is suspended and his deputy Alex Buttner ended Saturday's match against Villa with a tight hamstring.
The Dutchman did take part in an open training session on Monday, though, along with centre-backs Rio Ferdinand, Chris Smalling and Jonny Evans who did not feature at the weekend.
Moyes added: "We have defensive issues undoubtedly. I won't be giving out my team today but, as everybody is aware, we will have to make one or two changes."