This is a list of the Spanish PROMUSICAE Top 20 Singles number-ones of 1991.[1]
| Issue Date | Song | Artist |
|---|---|---|
| 5 January | "I've Been Thinking About You" | Londonbeat |
| 12 January | ||
| 19 January | ||
| 26 January | "Sadness Part I" | Enigma |
| 2 February | ||
| 9 February | ||
| 16 February | ||
| 23 February | ||
| 2 March | ||
| 9 March | ||
| 16 March | "The Grease Megamix" | John Travolta and Olivia Newton-John |
| 23 March | ||
| 30 March | ||
| 6 April | ||
| 13 April | ||
| 20 April | ||
| 27 April | ||
| 4 May | ||
| 11 May | ||
| 18 May | ||
| 25 May | ||
| 1 June | ||
| 8 June | "El 7 de Septiembre" | Mecano |
| 15 June | ||
| 22 June | ||
| 29 June | "Gypsy Woman (She's Homeless)" | Crystal Waters |
| 6 July | ||
| 13 July | "Aquest Any Si" | Varios |
| 20 July | "Gypsy Woman (She's Homeless)" | Crystal Waters |
| 27 July | ||
| 3 August | ||
| 10 August | ||
| 17 August | ||
| 24 August | "You Could Be Mine" | Guns N' Roses |
| 31 August | ||
| 7 September | ||
| 14 September | ||
| 21 September | "Asi Me Gusta" | Chimo Bayo |
| 28 September | ||
| 5 October | ||
| 12 October | ||
| 19 October | ||
| 26 October | ||
| 2 November | ||
| 9 November | "The Fly" | U2 |
| 16 November | "Black or White" | Michael Jackson |
| 23 November | ||
| 30 November | ||
| 7 December | ||
| 14 December | ||
| 21 December | ||
| 28 December" |