"Tangerine" is a folk rock song by the English band Led Zeppelin. Recorded in 1970, it is included on the second, more acoustic-oriented side of Led Zeppelin III (1970). The plaintive ballad reflects on lost love and features strummed acoustic guitar rhythm with pedal steel guitar.

The Yardbirds, with guitarist Jimmy Page, recorded an early version of the song in 1968, titled "Knowing That I'm Losing You". When it was released on the Page-produced 2017 album Yardbirds '68, Keith Relf's vocal was left out. "Tangerine" has been performed in concert by Led Zeppelin at different points in their career and has been recorded by other musicians.

"Tangerine" dates back to Page's time as lead guitarist with the Yardbirds. In April 1968, the group recorded demos for several songs at the Columbia Studios in New York City. Page biographer George Case notes that "Knowing That I'm Losing You" is very similar to "Tangerine" and suggests that Jackie DeShannon inspired the tune. Recordings from these sessions (with producer Manny Kellem) and the concert performance later used for Live Yardbirds: Featuring Jimmy Page were rejected for release at the time, but were issued in 2017 on the Yardbirds '68 compilation album produced by Page. While the demo recorded by the Yardbirds featured a vocal by Keith Relf, the 2017 release does not include it.

To develop material for a follow-up album to Led Zeppelin II, Page and singer Robert Plant took a working holiday at Bron-Yr-Aur, a rustic retreat in South Snowdonia, Wales. Plant in particular was inspired by the back-to-the-land trends in northern California and the British folk scene. Accompanied only by acoustic guitar, hand-claps, and harmonica, the pair created tunes that served as the basis for several songs on Led Zeppelin III and later albums. Although written earlier, "Tangerine" reflects this rural sensibility and journalist Nigel Williamson includes it with the acoustic material born of the Bron-Yr-Aur sojourn. Other earlier influences include songs recorded at Mickie Most's Donovan sessions, when John Paul Jones and Page were studio musicians.

The song begins with a guitar figure, then a pause to set the right tempo. The guitar proceeds with an A minor–G–D guitar progression. Page actually plays two guitar parts – one on a six-string and the other on a twelve-string Giannini Craviola acoustic guitar – which, due to the audio mixing, almost sound as one.

Plant then sings the first verse accompanied by the backing guitar chords:

Measuring a summer's day
I only find it slips away to grey
The hours, they bring me pain

Bassist John Paul Jones complements Page on mandolin.