Desu can mean:
- A Japanese copula (です), or word used to grammatically link a subject and predicate, often translated into English using the verb "to be"; see Copula (linguistics)#Japanese
- An abbreviation for Delaware State University
- An Internet meme originating from the television show Rozen Maiden, involving a character from the show who repeats the word "desu" (see above) as a verbal tic.
- Diplôme d'études supérieures universitaires (DESU or D.E.S.U.), a French academic grade