In Greek mythology, Iolaus (in Greek, Ἰόλαος) was a Theban divine hero, son of Iphicles, Heracles's nephew, and brother to Automedusa.

He was famed for being Heracles's nephew and for helping with some of his Labors, and also for being one of the Argonauts. Through his daughter Leipephilene he was considered to have fathered the mythic and historic line of the kings of Corinth, ending with Telestes.

A genus of Lycaenid butterfly has been named after him.

Read more about Iolaus:  Relationship With Heracles, Television