The Symphony No. 71 in B-flat major, Hoboken I/71, is a symphony by Joseph Haydn. It was composed by 1780.

The symphony is scored for flute, two oboes, bassoon, two horns and strings.

1. Adagio, ⁴
   ₄ – Allegro con brio, ³
   ₄
2. Adagio F major, ²
   ₄
3. Menuetto & Trio, ³
   ₄
4. Finale: Vivace, ⁴
   ₄

After dark string sonorities reminiscent of Sturm und Drang in the slow introduction, the Allegro begins with a very light galante theme which is interrupted periodically by more darkly colored strings. The transitional material is notable for its use of counterpoint.^[1]

The slow second movement is a theme with four variations and a coda. The second variation features a flute and bassoon duet over thirty-second notes and pizzicato bass. Triplet-sixteenths dominate the third variation. As usual, the final variation is recapitulatory, but here Haydn extends the variation with further development and a cadenza-like passage.^[1]

The trio of the minuet features solo sections for two violins against a pizzicato bass.^[1]

• Haydn: Chronicle and Works, 5 vols, (Bloomington and London: Indiana University Press, 1976-) v. 2, Haydn at Eszterhaza, 1766-1790
• Oxford Composer Companions: Haydn, ed. David Wyn Jones, Oxford University Press, 2002. ISBN 0-19-866216-5