This is a list of singles which have reached number one on the Irish Singles Chart in 1972. The chart issue date changed from Saturday to Friday effective in late June.
| Issue Date | Song | Artist | References |
|---|---|---|---|
| 1 January | "Slaney Valley" | Larry Cunningham | [1] |
| 8 January | "I'd Like To Teach The World To Sing (In Perfect Harmony)" | ||
| 15 January | |||
| 22 January | "The Men Behind the Wire" | Barleycorn | |
| 29 January | |||
| 5 February | |||
| 12 February | "Telegram Sam" | T. Rex | |
| 19 February | |||
| 26 February | |||
| 4 March | "Give Ireland Back to the Irish" | Paul McCartney | |
| 11 March | "Without You" | Nilsson | |
| 18 March | "Ceol An Ghrá" | Sandie Jones | |
| 25 March | "Without You" | Nilsson | |
| 1 April | "Three Leafed Shamrock" | John Kerr | |
| 8 April | "Broken Marriage Vows" | Big Tom And The Mainliners | |
| 15 April | |||
| 22 April | "Amazing Grace" | Royal Scots Dragoon Guards | |
| 29 April | "Sunday Bloody Sunday" | Paddywagon | |
| 6 May | "What Do I Do" | Sandie, Joe and Dixies | |
| 13 May | "A Thing Called Love" | Johnny Cash | |
| 20 May | |||
| 27 May | |||
| 3 June | |||
| 10 June | "Metal Guru" | T. Rex | |
| 16 June | "Vincent" | Don McLean | |
| 22 June | |||
| 29 June | "Ooh-Wakka-Doo-Wakka-Day" | Gilbert O'Sullivan | |
| 6 July | |||
| 13 July | |||
| 20 July | [2] | ||
| 20 July | "Sylvia's Mother" | ||
| 27 July | |||
| 3 August | |||
| 10 August | |||
| 17 August | |||
| 24 August | |||
| 31 August | |||
| 7 September | "The Gypsy" | Dermot Henry | |
| 14 September | |||
| 21 September | "Mama Weer All Crazee Now" | Slade | |
| 28 September | |||
| 5 October | T. Rex | ||
| 12 October | |||
| 19 October | "How Can I Be Sure?" | David Cassidy | |
| 26 October | "Clair" | Gilbert O'Sullivan | |
| 2 November | "Mouldy Old Dough" | Lieutenant Pigeon | |
| 9 November | "Clair" | Gilbert O'Sullivan | |
| 16 November | |||
| 23 November | |||
| 30 November | |||
| 7 December | "My Ding-A-Ling" | Chuck Berry | |
| 14 December | |||
| 21 December | "Whiskey in the Jar" | Thin Lizzy | |
| 28 December |