Star-Lord (Peter Jason Quill) is a superhero appearing in American comic books published by Marvel Comics. Created by Steve Englehart and Steve Gan, the character first appeared in Marvel Preview #4 (January 1976). The son of human Meredith Quill and Spartoi J'son, Peter Quill assumes the mantle of Star-Lord, an interplanetary policeman.

The character played prominent roles in the comic book storylines "Annihilation" (2006) and "Annihilation: Conquest" (2007), "War of Kings" (2008), The Thanos Imperative (2009), and Old Man Quill (2019). He became the leader of the space-based superhero team Guardians of the Galaxy in the 2008 relaunch of the comic of the same name. He has been featured in a variety of associated Marvel merchandise, including animated television series, toys and trading cards.

Chris Pratt portrays the character in the Marvel Cinematic Universe films Guardians of the Galaxy (2014), Guardians of the Galaxy Vol. 2 (2017), Avengers: Infinity War (2018), Avengers: Endgame (2019), Thor: Love and Thunder, The Guardians of the Galaxy Holiday Special (both 2022), and Guardians of the Galaxy Vol. 3 (2023). Wyatt Oleff portrays a young Peter Quill in the first two Guardians of the Galaxy films. Quill also appeared in the Disney+ animated series What If...? (2021).

Steve Englehart had plans for the character that went unrealized. He later reflected on his website:

I conceived something very large. My hero would go from being an unpleasant, introverted jerk to the most cosmic being in the universe, and I would tie it into my then-new interest in Astrology. After his earthbound beginning, his mind would be opened step by step, with a fast-action story on Mercury, a love story on Venus, a war story on Mars, and so on out to the edge of the solar system, and then beyond. But—after his earthbound beginning, where I established him as an unpleasant, introverted jerk, I left Marvel, so no one ever saw what he was to become.

Englehart would later state that the story on Jupiter would be about Government, and that his version of the character was not a part of the Marvel universe and was "completely standalone".

The character first appeared in the black-and-white magazine publication Marvel Preview #4 (Jan 1976). Star-Lord continued to appear in Marvel Preview, with writer Chris Claremont revamping the character and using science fiction adventure stories like the Heinlein juveniles for inspiration. Heinlein's lawyers threatened legal action over the cover to Marvel Preview #11, which featured a blurb that described the content as "a novel-length science fiction spectacular in the tradition of Robert A. Heinlein", leading to the issue being pulled and reprinted. The story in #11 was the first teaming of the celebrated X-Men creative trio of writer Chris Claremont, penciller John Byrne, and inker Terry Austin. Star-Lord made sporadic appearances over the next few years in the titles Marvel Super Special, Marvel Spotlight, and Marvel Premiere. The Marvel Spotlight installments, which were Star-Lord's first appearance in a traditional comic book format, served to consolidate the separate but complementary origin stories from his two appearances in Marvel Preview. In February 1982, a color reprint of the black-and-white Star-Lord story from Marvel Preview #11 was published with a new framing sequence by Claremont and artist Michael Golden.

The character returned in Thanos #8–12 (May–Sept. 2004) and Annihilation #1-6 (2006). The following year, he received a four issue eponymous title (Annihilation: Conquest – Star-Lord) leading into the "Annihilation: Conquest" crossover storyline, in which he played a central role. Spinning out of "Annihilation: Conquest", a second volume of Guardians of the Galaxy featured a team of characters from the crossover who were led by Star-Lord for the duration of the title's 25-issue run. Plot lines from that series were concluded in The Thanos Imperative mini-series.