Black propaganda is propaganda that purports to be from a source on one side of a conflict, but is actually from the opposing side. It is typically used to vilify, embarrass or misrepresent the enemy. It contrasts with grey propaganda, the source of which is not identified, and white propaganda, in which the real source is declared. The term is also sometimes used as a synonym for particularly malicious wartime propaganda or falsification of information that is captured by an enemy.

Black propaganda may be generated by altering genuine enemy propaganda in such a way as to distort its message. This is a particularly powerful tool if the target audience has a poor understanding of the language of the enemy.