List of Gaon Digital Chart number ones of 2015
The Gaon Digital Chart, part of Gaon Music Chart, is a chart that ranks the best-performing songs in South Korea. The data is collected by the Korea Music Content Association. It consists of weekly, monthly and yearly charts. Below is a list of songs that topped the weekly and monthly charts. The Digital Chart ranks songs according to their performance on the Gaon Download, Streaming, and BGM charts.
Weekly charts
| Indicates best-performing single of 2015 |
| Week end date | Song | Artist |
| January 3 | "Up & Down" | EXID |
| January 10 | "Déjà-Boo" | Jonghyun featuring Zion.T |
| January 17 | "Fire" | Mad Clown featuring Jinsil of Mad Soul Child |
| January 24 | "I Have To Forget You" | Jeong Seung-hwan and Park Yoon-ha |
| January 31 | "Cry Again" | Davichi |
| February 7 | "Just" | Zion.T and Crush |
| February 14 | "You from the Same Time" | Naul |
| February 21 | "You from the Same Time" | Naul |
| February 28 | "You from the Same Time" | Naul |
| March 7 | "Love Mash" | MC Mong featuring Chancellor |
| March 14 | "Love Mash" | MC Mong featuring Chancellor |
| March 21 | "Snow of April" | Huh Gak |
| March 28 | "Puss" | Jimin with Iron |
| April 4 | "Only You" | Miss A |
| April 11 | "Only You" | Miss A |
| April 18 | "Who's Your Mama?" | Park Jin-young featuring Jessi |
| April 25 | "Who's Your Mama?" | Park Jin-young featuring Jessi |
| May 2 | "Loser" | Big Bang |
| May 9 | "Loser" | Big Bang |
| May 16 | "Loser" | Big Bang |
| May 23 | "Heart" | IU |
| May 30 | "View" | Shinee |
| June 6 | "Bang Bang Bang" | Big Bang |
| June 13 | "Love Me Right" | Exo |
| June 20 | "Shouldn't Have" | Baek A-yeon featuring Young K |
| June 27 | "Shake It" | Sistar |
| July 4 | "If You" | Big Bang |
| July 11 | "Party" | Girls' Generation |
| July 18 | "Come and Goes" | hyukoh |
| July 25 | "Yanghwa BRDG" | Zion.T |
| August 1 | "Wi Ing Wi Ing" | hyukoh |
| August 8 | "Let's Not Fall In Love" | BigBang |
| August 15 | "Let's Not Fall In Love" | BigBang |
| August 22 | "Oppa's Car" | Incredivle, Tablo, and Jinusean |
| August 29 | "Leon" | Park Myung-soo and IU |
| September 5 | "Leon" | Park Myung-soo and IU |
| September 12 | "Leon" | Park Myung-soo and IU |
| September 19 | "My Type" | iKON |
| September 26 | "Get Some Air" | Gary featuring Miwoo |
| October 3 | "Love Again" | Im Chang-jung |
| October 10 | "I" | Taeyeon featuring Verbal Jint |
| October 17 | "No Make Up" | Zion.T |
| October 24 | "Twenty-three" | IU |
| October 31 | "Twenty-three" | IU |
| November 7 | "Boys and Girls" | Zico featuring Babylon |
| November 14 | "Let's Hug" | 4Men |
| November 21 | "Apology" | iKON |
| November 28 | "A Little Girl" | Oh Hyuk |
| December 5 | "Daddy" | Psy featuring CL |
| December 12 | "Eureka" | Zico featuring Zion.T |
| December 19 | "This Is Love" | Yoon Mi-rae |
| December 26 | "Again" | Turbo |
Monthly charts
| Month | Song | Artist | |
| "Fire" | Mad Clown featuring Jinsil of Mad Soul Child | ||
| "You from the Same Time" | Naul | ||
| "Love Mash" | MC Mong featuring Chancellor | ||
| "Only You" | Miss A | ||
| "Loser" | BigBang | ||
| "Bang Bang Bang" | BigBang | ||
| "If You" | BigBang | ||
| "Let's Not Fall In Love" | BigBang | ||
| "Leon" | Park Myung-soo and IU | ||
| "I" | Taeyeon featuring Verbal Jint | ||
| "Boys and Girls" | Zico featuring Babylon | ||
| "Daddy" | Psy featuring CL |