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 1979.
| Issue date | Song | Artist(s) | Ref. |
|---|---|---|---|
| January 1 | "Chameleon Army" | Pink Lady | [1] |
| January 8 | |||
| January 15 | |||
| January 22 | |||
| January 29 | "" | ||
| February 5 | |||
| February 12 | |||
| February 19 | |||
| February 26 | "" | ||
| March 5 | |||
| March 12 | "" | Hideki Saijo | |
| March 19 | |||
| March 26 | |||
| April 2 | |||
| April 9 | |||
| April 16 | "" | Judy Ongg | |
| April 23 | |||
| April 30 | |||
| May 7 | |||
| May 14 | |||
| May 21 | |||
| May 28 | |||
| June 4 | |||
| June 11 | |||
| June 18 | "" | ||
| June 25 | |||
| July 2 | |||
| July 9 | |||
| July 16 | |||
| July 23 | "" | Sachiko Kobayashi | |
| July 30 | "" | Masashi Sada | |
| August 6 | |||
| August 13 | |||
| August 20 | |||
| August 27 | |||
| September 3 | |||
| September 10 | |||
| September 17 | |||
| September 24 | |||
| October 1 | |||
| October 8 | "" | ||
| October 15 | |||
| October 22 | |||
| October 29 | "" | Masashi Sada | |
| November 5 | |||
| November 12 | |||
| November 19 | |||
| November 26 | |||
| December 3 | |||
| December 10 | "IhÅjin" | Sayuri Kume | |
| December 17 | |||
| December 24 | |||
| December 31 |