Shatterday is a collection of short stories by American author Harlan Ellison.

In the introduction, Ellison states that the stories reflect an underlying theme of fear of human frailty and ugliness.

Each story has an introduction, ranging from a single sentence to several pages long.

It was also voted in a 1999 online poll of Locus readers to be the best short story of all time.

Other stories have been reprinted in omnibus collections such as The Essential Ellison: a 35-Year Retrospective and Dreams With Sharp Teeth.