Scorpio resembles, quite noticeably, a scorpion's tail, and a vague body . According to Greek mythology, it corresponds to the scorpion which was sent by Gaia (or possibly the goddess Hera) to kill the hunter Orion, the scorpion rising out of the ground at the goddess' command to attack. Although the scorpion and Orion appear together in this myth, the constellation of Orion is almost opposite to Scorpius in the night sky. It has been suggested that this was a divine precaution to forestall the heavenly continuation of the feud.

In many versions, however, Apollo sent the scorpion after Orion, having grown jealous of Artemis' attentions to the man. Later, to apologize for killing her friend, Apollo then helped Artemis hang Orion's image in the night sky. However, the scorpion was also placed up there, and every time it appears on the horizon, Orion starts to sink into the other side of the sky, still running from the attacker.

Scorpius also appears in one version of the story of Phaethon, the mortal son of Helios, the sun. Phaeton asked to drive the sun-chariot for a day. Phaeton lost control of the chariot. The horses, already out of control, were scared by the great celestial scorpion with its sting raised to strike, and the inexperienced boy lost control of the chariot, as the sun wildly went about the sky (this is said to have formed the constellation Eridanus). Finally, Zeus struck him down with a thunderbolt to stop the rampage.

The Chinese included these stars in the Azure Dragon, a powerful but benevolent creature whose rising heralded spring.

In Maori mythology, this constellation can be Maui's magic jawbone (used to fish up the North Island of New Zealand), the front of Tama-rereti's waka/canoe (used to ferry the stars into the sky) or one of the posts Tane used to hold Ranginui (the sky-father) in the sky. While three posts (Sirius, Matariki/The pleides and Orion) hold up the top half of Ranginui, only a single post (Scorpius) supports the lower half of his body. It therefore appears bent under the weight.