Loki is a fascinating figure in Norse mythology. There are many different aspects to his personality, and he often does more harm than good for those around him. Many people wonder if the Marvel Cinematic Universe (MCU) depicts him accurately. For example, people wonder if Loki and Thor are really brothers.
Loki and Thor are not brothers in Norse mythology. Loki’s parents were Farbauti, the Frost Giant, and Laufey, while Thor’s parents were Odin and Jörd, a giantess. In Norse mythology, Loki is portrayed as Odin and Thor’s companion, meaning he didn’t have blood relations with either of the two.
Thanks largely to the MCU, many people have a different idea about the relationship between Loki and Thor, but the truth is that they don’t have any familial relationship in Norse mythology. Read on to learn more about the origin of this misconception that they are brothers and to gain insights into their actual relationship.
Also see Is Thor Immortal In Norse Mythology? to learn more.

Who Is Loki’s Brother in Norse Mythology?
Helblindi and Byleistr are Loki’s brothers in Norse mythology, not Thor. Both of his brothers were Jötnar, just like Loki. Their mother’s name was Laufey, although, in some versions of the myths, she’s referred to as Nál, which comes from an Icelandic word that means “needle.”
However, Helblindi and Byleistr came from an unknown father who was reportedly either a Frost Giant or a Rime-Thurses.
Although the more popular interpretation of Norse mythology is that Thor and Loki are not brothers, many people assume that they are.
Where does the misconception that Loki and Thor are brothers come from? The main reason is that the Marvel Cinematic Universe.
In Norse mythology, Odin and Loki swore an oath that bonded them like brothers. Notably, Loki swore that he would not harm Odin or any of his children.
Similarly, Odin swore not to harm Loki. They mixed their blood and took solemn oaths, making them sworn brothers.
Additionally, Loki offers his services as a skilled craftsman-god and helpful adventurer for Thor’s endeavors on Earth or Asgard. That was their relationship.
However, in the Marvel Universe, Loki is adopted by Odin after being abandoned as a child. In return for being taken in by his new family, he offers to help Thor when the God of Thunder needs such assistance and guidance on Earth or Asgard.
Since more people watched the Thor and Avengers movies than have read the ancient Norse myths, the Marvel version stuck, and now, most people assume the two gods are brothers.
Also see Is Thor Good or Bad in Norse Mythology? to learn more.

Who Are Loki’s Other Family Members in Norse Mythology?
In Norse mythology, Loki’s other family includes his wife, Sigyn, and their children, Narfi and Vali. He also had Fenrir, the wolf, Hel (or Hela), the ruler of Hel, and Jörmungandr, the world serpent, with the giantess Angrboda. He is also the mother of Svaðilfari, who he conceived in horse form.
According to both the Poetic Edda and the Prose Edda, Fenrir kills Odin at Ragnarok.
In addition, Loki bore Sleipnir to Svaðilfari, the horse of a giant who came to Asgard to build up the walls in exchange for Freya’s hand in marriage.
In contrast, Thor’s wife in Norse mythology is Sif, but it’s unclear if the two of them ever had any sons. Thor did help raise Sif’s first son, Ullr, and the two of them had a daughter named Thrud.
He met Járnsaxa at Utgardr during one adventure where she gave birth to their son Magni. Thor was left holding onto the child when his companions ran off in terror because they thought it might be dangerous for them to travel together now that he had fathered an offspring on such an unusual woman and had a giantess in his company.
Thor also has another son, Modi, but his mother is never named in the sagas.
Also see Who is Thor’s Wife in Norse Mythology? to learn more.
Who Are Thor’s Siblings in Norse Mythology?
Accounts of Thor’s parentage vary, but assuming he’s Odin’s son, Thor’s siblings are Baldr, Höðr, Víðarr, and Váli. The eldest was the god Baldr, who was the son of Odin and Frigg and was mistakenly killed by his twin Höðr. Váli avenges Baldr’s death, while Víðarr avenges their father’s death.
Although there’s no mention of Thor’s siblings in the Poetic Edda, they appear to have been known among Scandinavians in the Viking Age.
Most notably, Snorri Sturluson mentions them as part of a list of male descendants from Nór under each king’s name, apparently as a formality because their fame was already established by then.
Snorri mentions Baldr only briefly—a single sentence that tells how he was generally regarded as kind, generous-spirited and beautiful. The account goes into much more detail about his death with vignettes about his funeral pyre, leaving a light so great that it could be seen in the world.
Baldr is portrayed as one who projectiles could never hurt – they rebounded upon hitting him. The only exception was mistletoe. According to Snorri’s account, Loki tricked Höðr into throwing a spear with mistletoe at Baldr, leading to Baldr’s death.
Baldr’s death was a heavy blow to Odin. Baldr had been his favorite son, and Odin gave an emotional speech about how he looked forward to Baldr becoming king after himself.
Váli then takes up this role in Snorri’s account of Norse mythology; most notably, he avenges his brother by killing his murderer, Höðr, According to some accounts, Váli was born and grew to become an adult within a day.
Víðarr was Thor’s only full-brother, and it was with him that Thor had a showdown during the events of Ragnarök.
Frequently Asked Questions
Is Loki Thor’s Cousin?
Loki isn’t Thor’s cousin. Loki’s father, Farbauti, and Thor’s father, Odin, are unrelated. Similarly, Norse mythology doesn’t point out whether their mothers, Laufey and Jörd, had any close blood relations. Aside from his wife and children, Loki has no blood relatives among the Aesir.
Is Loki Thor’s Uncle?
Biologically, Loki isn’t Thor’s uncle. In Norse mythology, Thor’s father, Odin, had two brothers – Vili, called “the champion”, and Ve, who had no particular nickname. Therefore, Vili and Ve are Thor’s uncles, not Loki. Loki and Thor were not related in any way.
Despite the oath between Loki and Odin, it cannot be said that Loki was Thor’s uncle since he was neither related to Thor’s father nor mother.
Conclusion
Loki and Thor are not brothers in Norse mythology. Loki’s parents were Farbauti and Laufey. In contrast, Thor’s parents were Odin and Jörd.