| O | — | 12 October 2018 | Album |
| O cantor do sertão: O sertão de Victor & Leo | — | 2018 | Album |
| Oblivion | — | 23 August 2015 | Album |
| Observasi Transisi | — | 6 November 2025 | Album |
| Ode Buat Kota | — | 8 March 2010 | Album |
| Ode to Billie Joe / Touch ’em With Love | — | 2008 | Album |
| Of Merah Putih | — | 17 August 2023 | Single |
| Offerings to Rangda | — | 1997 | Album |
| Oh Boy Classics Presents Conway Twitty | — | 26 June 2001 | Album |
| Oh Happy Day | — | 1970 | Album |
| Oh Malaysia | — | 1963 | EP |
| Oh to Be in Love | — | 18 March 2022 | EP |
| Oh Well | — | 30 September 2014 | Single |
| Oi Its A World Invasion Volume 2 | — | December 2014 | Album |
| Oil Spill | — | 2 August 2024 | EP |
| OK LAH | — | 1 January 2014 | Single |
| Old Golden Throat | — | June 1968 | Album |
| Ol’ Rockin’ Ern | — | September 1957 | Album |
| Ombak Asmara | — | 20 May 2016 | Single |
| Omega | — | 5 June 2017 | Single |
| Omnipotent Pyramid Poem | — | 2 June 2014 | EP |
| Omomo punk | — | 29 March 2021 | Single |
| Omong Kosong | — | 1 June 1987 | Album |
| On Different Days | — | 25 June 2021 | Album |
| On Our Own | — | 27 May 2026 | Single |
| On the Trail | — | 1994 | Album |
| On This Holiday | — | 26 October 2018 | Album |
| Once Upon A Christmas | — | 11 December 2024 | Single |
| Once Upon a Christmas | — | December 1984 | Album |
| One | — | 22 January 2007 | Album |
| One More Day | — | 6 February 2001 | Album |
| One More Light | — | 20 May 2024 | Single |
| One More Shot | — | 14 June 2013 | Album |
| One of a Kind | — | 1977 | Album |
| One Way Love | — | 1996 | Album |
| Online 24/7 | — | 2 February 2026 | EP |
| Only You | — | 22 February 2019 | Single |
| ONS (live studio session) | — | 4 October 2019 | Single |
| Ontime | — | 10 October 2024 | Single |
| Oo.. Lea... Leo...!!! | — | 3 September 1993 | Album |
| Ookami Cafe | — | 21 September 2022 | EP |
| Oouuh | — | 26 November 2021 | Single |
| Opini | — | 1982 | Album |
| Opus Contra Naturam | — | 14 June 2017 | Album |
| Orang Kita | — | 9 September 2022 | Single |
| Orang Miskin | — | 5 January 2022 | Single |
| Orang Pinggiran | — | 1995 | Album |
| Orang yang Paling Kubenci | — | 18 December 2020 | Single |
| Orange Genome | — | 1 October 2018 | Single |
| OREO | — | 18 March 2019 | Single |
| Original Javanese Music, Vol. 1: Gamelan Music: Gending‐gending instrumentalia | — | 1992 | Album |
| Original Peterpan In House Mix | — | 2005 | Album |
| Oscillation | — | 10 May 2018 | Single |
| Oscillation / Crayola Eyes | — | 21 April 2018 | Single |
| Oslan Husein | — | 1964 | Album |
| OST Antologi Rasa | — | 8 February 2019 | Single |
| Ost. Menggapai Harapan | — | 12 April 1996 | Single |
| Our Biggest Thing Ever | — | 25 January 2012 | Album |
| Out of Love | — | 22 September 2010 | Single |
| Out of Shell | — | 2006 | Album |
| Outer Space | — | 26 April 2024 | Single |
| Outtaspace | — | 4 July 2024 | Album |
| Over You | — | 2 October 2015 | Single |
| Overdrive Dreams | — | 28 January 2022 | EP |
| Overture of Storms (Unknown God Theme) | — | 8 July 2021 | Single |