No. Eminem is not in the 2009 movie The Hangover. See full cast of the movie on IMDb.
Here is a list of Eminem cameos in movies:
Da Hip-Hop Witch 2000
The Wash 2001
Funny People 2009
The Interview 2014
Big-budget Hollywood movies are typically so formulaic that you can predict every beat within the first five minutes. Which is why, in most cases, a surprise are welcome. That's where the celebrity cameos come in.
From Bill Murray in Zombieland to Eminem in Funny People, celebs can make an ultimately standard flick more memorable. Here are the 25 Most Unexpected Celebrity Cameos in Movies shared by Complex.com.