Skitt's Law is an adage in Internet culture that originated on Usenet. Its precise wording is a matter of debate, but its general intent is that someone who corrects another's grammar or spelling mistake is bound to make such a mistake in the very post that corrects. In one phrasing, "Spelling or grammar flames always contain spelling or grammar errors."

Although the law originated in the Usenet newsgroup alt.usage.english, its authorship is shrouded in the mists of unarchived Usenet messages. (Skitt , an alt.usage.english denizen, has denied authorship.) It is sometimes attributed to Bob Lieblich or, more often, to Erin McKean , both incorrectly. It is also known as Naruki's law in the User Friendly forums.

Some view the law as a curse.