The midfielder has warned his team-mates to be wary of a revival from the Old Trafford club after being paired with the Premier League champions in Friday's Champions League draw
Pep Guardiola's side will face the reigning English champions in the quarter-finals of the Champions League following Friday's draw in Nyon, with the Bavarians sure to be favourites ahead of the tie.
United have endured a torrid time in David Moyes's first campaign and sit seventh in the league, while they required a stirring comeback to defeat Olympiakos 3-0 (Agg 3-2) to reach the last eight in Europe.
In contrast, Champions League holders Bayern have made a seamless transition to life after Jupp Heynckes and Guardiola's men could lift the Bundesliga title as early as this weekend if they win and other results go in their favour.
But Kroos - who has been regularly linked with a move to Old Trafford this coming summer - with his contract set to expire in the summer of 2014 - will not be taking the tie lightly.
He said on his official Facebook page: "A very interesting draw for us! We shouldn't measure Man U by their current position in the English table."
Bayern and United have considerable history when it comes to the Champions League, with United defeating the Bundesliga champions 2-1 in the famous 1999 final.
However, it was the Bavarians who came out on top in the most recent encounter between the two sides after a 4-4 aggregate draw in the 2010 quarter-finals, with FCB going through on away goals.
The first leg of the last eight tie will be played one April 1 or 2, with the return leg scheduled for April 8 or 9.