The highest-selling singles in Japan are ranked in the Oricon Singles Chart, which is published by Oricon Style magazine. The data are compiled by Oricon based on each singles' physical sales. This list includes the singles that reached the number one place on that chart in 1988.
| Issue date | Song | Artist(s) | Ref. |
|---|---|---|---|
| January 4 | "Glass no Jūdai" | Hikaru Genji | [1] |
| January 11 | |||
| January 18 | |||
| January 25 | "Kaze no Lonely Way" | Kiyotaka Sugiyama | |
| February 1 | "Stranger Tonight" | Yoko Oginome | |
| February 8 | "Al-Mauj" | Akina Nakamori | |
| February 15 | |||
| February 22 | "Kanpai" | Tsuyoshi Nagabuchi | |
| February 29 | "You're My Only Shinin' Star" | Miho Nakayama | |
| March 7 | "" | Yoko Minamino | |
| March 14 | |||
| March 21 | "" | Hikaru Genji | |
| March 28 | |||
| April 4 | |||
| April 11 | |||
| April 18 | |||
| April 25 | "Marrakech" | Seiko Matsuda | |
| May 2 | "" | Yui Asaka | |
| May 9 | "Stardust Dream" | Yoko Oginome | |
| May 16 | "C-GIRL" | Yui Asaka | |
| May 23 | |||
| May 30 | "Tattoo" | Akina Nakamori | |
| June 6 | |||
| June 13 | "Fu-ji-tsu" | Shizuka Kudo | |
| June 20 | |||
| June 27 | "" | Yoko Minamino | |
| July 4 | "" | Hikaru Genji | |
| July 11 | |||
| July 18 | "" | Shonentai | |
| July 25 | "Mermaid" | Miho Nakayama | |
| August 1 | "Angel" | Kyosuke Himuro | |
| August 8 | |||
| August 15 | |||
| August 22 | |||
| August 29 | "Cecil" | Yui Asaka | |
| September 5 | "Daybreak" | Otokogumi | |
| September 12 | |||
| September 19 | "" | Seiko Matsuda | |
| September 26 | "Daybreak" | Otokogumi | |
| October 3 | "Mugon... Iroppoi" | Shizuka Kudo | |
| October 10 | |||
| October 17 | "" | Yoko Minamino | |
| October 24 | "" | Hikaru Genji | |
| October 31 | |||
| November 7 | "" | Tsuyoshi Nagabuchi | |
| November 14 | |||
| November 21 | "" | Shonentai | |
| November 28 | "Witches" | Miho Nakayama | |
| December 5 | "Tonbo" | Tsuyoshi Nagabuchi | |
| December 12 | |||
| December 19 | |||
| December 26 |