The ostrich guitar or ostrich tuning is a type of trivial tuning. It assigns one note to all strings, e.g. E-E-e-e-e'-e' or D-D-D-D-d'-d'. The term "ostrich guitar" was coined by the Velvet Underground's Lou Reed after the pre-Velvet Underground song "The Ostrich" by Lou Reed and the Primitives, on which he first recorded using this tuning, the first known commercial composition to make use of a trivial guitar tuning.

Lewis Allan Reed was an American musician and songwriter. He was the guitarist, singer, and principal songwriter for the rock band The Velvet Underground and had a solo career that spanned five decades. Although not commercially successful during its existence, the Velvet Underground came to be regarded as one of the most influential bands in the history of underground and alternative rock music. Reed's distinctive deadpan voice, poetic and transgressive lyrics, and experimental guitar playing were trademarks throughout his long career.