In J. R. R. Tolkien's fictional legendarium, Beleriand (Sindarin pronunciation: [bɛˈlɛ.ri.and]) was a region in northwestern Middle-earth during the First Age. Events in Beleriand are described chiefly in his work The Silmarillion: It tells the story of the early Ages of Middle-earth, in a style similar to that of the epics of Nordic literature—stories pervaded by a tone of impending doom. Beleriand also appears in the works The Book of Lost Tales, The Children of Húrin, and The Lays of Beleriand.

In Tolkien's early writing, he coined many prospective names for the region. Among them were Broceliand, the name of an enchanted forest in medieval romance, and Ingolondë—a play on the name England—when he hoped to root a mythology for England in the region. The scholar Gergely Nagy looked at the prose of the Silmarillion and found what may be evidence of the structure and syntax of Beleriand's poetry.

Events in Beleriand are described chiefly in the second half of the Quenta Silmarillion, which tells the story of the early ages of Middle-earth in a style similar to the epic hero tales of Norse mythology. Beleriand also appears in the works The Book of Lost Tales, The Children of Húrin, and in the epic poems of The Lays of Beleriand.

The land is occupied by Teleri Elves of King Thingol from the east, who founded the city of Menegroth in the forest realm of Doriath. Other Elves, the Vanyar and Noldor, cross the Belegaer sea to Valinor. Some of the Noldor return to Beleriand to retrieve the Silmarils from the evil Vala Morgoth, but they are resented by the Teleri. Later, Men arrive from the east. Morgoth gathers an army of Orcs, Balrogs and other monsters in his fortress of Angband beneath the Thangorodrim mountains in the north of Beleriand, and attacks the Elves repeatedly. Despite the threat, Thingol refuses to fight alongside the Noldor. One by one, the realm of Doriath as well as the Noldor kingdoms Nargothrond and Gondolin fall to assaults, assisted by betrayals and disputes among Elves, Men, and Dwarves. Finally, Earendil crosses the Belegaer Sea to ask the Valar to stop Morgoth. They send an army to overcome Morgoth in the War of Wrath. This ends the First Age of Middle-earth: Angband is destroyed, and Morgoth is banished to the void. Beleriand's inhabitants flee, and much of Beleriand sinks into the sea. Only a small section of the eastern edge of Beleriand survives, including part of the Ered Luin (Blue Mountain) range and the land of Lindon, which became part of the far northwestern shore of Middle-earth.

Beleriand is a region in the far northwest of Middle-earth, bordering the great sea, Belegaer. It is bounded to the north by the Ered Engrin, the Iron Mountains, and to the east by the Ered Luin, the Blue Mountains.

Beleriand had many different names in Tolkien's early writings, including Broceliand, the name of an enchanted forest in medieval romance, Golodhinand, Noldórinan ("valley of the Noldor"), Geleriand, Bladorinand, Belaurien, Arsiriand, Lassiriand, and Ossiriand (later used for the easternmost part of Beleriand).

One of Beleriand's early names was Ingolondë, a play on "England", part of Tolkien's long-held but ultimately unsuccessful aim to create what Shippey calls "a mighty patron for his country, a foundation-myth more far-reaching than Hengest and Horsa, one to which he could graft his own stories." Tolkien's aim had been to root his mythology for England in the scraps of names and myths that had survived, and to situate it in a land in the northwest of the continent, by the sea.

Shippey writes that the Quenta Silmarillion has a tightly-woven plot, each part leading ultimately to tragedy. There are three Hidden Elvish Kingdoms in Beleriand, founded by relatives, and they are each betrayed and destroyed. The Kingdoms are each penetrated by a mortal Man, again all related to each other; and the sense of doom, which Shippey glosses as "future disaster", hangs heavy over all of the characters in the tale.