Steyr (German: [ˈʃtaɪɐ] ⓘ; Central Bavarian: Steia) is a statutory city, located in the Austrian federal state of Upper Austria.

The city is situated in the Traunviertel region, with the two rivers Steyr and Enns flowing through it and meeting near the town centre beneath Lamberg Castle and St Michael's Church.

The Otokars controlled the iron mining at Erzberg and made their residence at Steyr a centre of medieval courtly culture and Middle High German poetry.

The town privileges and market rights were confirmed by Rudolf's son King Albert I in 1287 and the citizens further on benefitted of Steyr's preferred position within the iron trade all over the Holy Roman Empire and especially with the Republic of Venice.

In the 13th and 14th century, Steyr was a centre of the Christian Waldensian movement and a location of the inquisitorial persecutions led by the Catholic cleric Petrus Zwicker (d. 1403).

Including the Steyr automobile branch from 1915 it was renamed Steyr-Werke AG in 1926 and formed a large industrial conglomerate by the merger with Austro-Daimler and Puch in 1934.

The Nazi authorities incorporated the armament industry into the vast Reichswerke Hermann Göring conglomerate, including the construction of the Steyr-Münichholz subcamp of forced labourers, part of the Mauthausen network.

A major producer of arms and military vehicles during World War II, Steyr became a target of Allied bombing raids to knock out its factories.

In two major attacks by the US Fifteenth Air Force during the "Big Week" on 23 and 24 February 1944, much of the town was badly damaged, but the factories continued to function until near the end of the war.

The city was a meeting point on 9 May 1945, when units of the 5th Guards Airborne of the Red Army and black troops of the US 761st Tank Battalion along with the 71st Infantry Division contacted each other on the bridge over the Enns River.

Steyr has had a number of well-known residents or visitors, including Franz Schubert (1797–1828), who wrote his Trout Quintet there while on holiday in 1819, and composer Anton Bruckner (1824–1896), organist at the local parish church.