This is a list of number one singles on the Billboard Japan Hot 100 chart in Japan in 2011. The week's most popular songs in Japan, ranked by the Hanshin Corporation and based on radio airplay measured by Plantech and sales data as compiled by SoundScan Japan.[1] [2]
| Date | Song | Artist | |
|---|---|---|---|
| January 3 | "A Winter Fairy Is Melting a Snowman" | Kaela Kimura | |
| January 17 | "Toilet no Kamisama" | Kana Uemura | |
| January 24 | "Dada" | Radwimps | |
| January 31 | "If" | French Kiss | |
| February 7 | "Why? (Keep Your Head Down)" | Tohoshinki | |
| February 14 | "Ultimate Wheels" | KAT-TUN | |
| February 21 | "Each Other's Way (Tabi no Tochū)" | Exile | |
| February 28 | "Sakura no Ki ni Narō" | AKB48 | |
| March 7 | "Lotus" | Arashi | |
| March 14 | "Eternal" | Jin Akanishi | |
| March 21 | "Yume Tamago" | NYC | |
| March 28 | "Shūmatsu Not Yet" | Not Yet | |
| April 4 | "Utsukushiki Hitobito no Uta" | Maximum the Hormone | |
| April 11 | "Born This Way" | Lady Gaga | |
| April 18 | "Kazoe Uta" | Mr. Children | |
| April 25 | "Sayonara Kizu Darake no Hibi yo" | B'z | |
| May 2 | "T.W.L" | Kanjani Eight | |
| May 9 | "Mr. Taxi" | Girls' Generation | |
| May 16 | |||
| May 23 | "My Home" | Kanjani Eight | |
| May 30 | "White" | KAT-TUN | |
| June 6 | "Everyday, Kachūsha" | AKB48 | |
| June 13 | |||
| June 20 | "365 Nichi Kazoku" | Kanjani Eight | |
| June 27 | "Time" | ||
| July 4 | "Flower" | ||
| July 11 | "Over" | ||
| July 18 | "Naminori Kakigōri" | Not Yet | |
| July 25 | "Fui ni" | ||
| August 1 | "Superstar" | Tohoshinki | |
| August 8 | "Pareo wa Emerald" | ||
| August 15 | "Run for You" | KAT-TUN | |
| August 22 | "Everybody Go" | ||
| August 29 | "Tsubusa ni Koi" | Kanjani Eight | |
| September 5 | "Flying Get" | AKB48 | |
| September 12 | "Kazoku ni Narō yo" | ||
| September 19 | "Niji no Uta" | ||
| September 26 | "Rising Sun/Itsuka Kitto…" | Exile | |
| October 3 | "Magic Power" | Hey! Say | JUMP |
| October 10 | "Bo Peep Bo Peep" | ||
| October 17 | "Omoidasenakunaru Sono Hi Made" | ||
| October 24 | "XXX" | ||
| October 31 | "Zero" | ||
| November 7 | "Kaze wa Fuiteiru" | AKB48 | |
| November 14 | "Meikyū Love Song" | Arashi | |
| November 21 | "Okie Dokie" | SKE48 | |
| November 28 | "Sexy Zone" | ||
| December 5 | "Anata e/Ooo Baby" | Exile | |
| December 12 | "Birth" | KAT-TUN | |
| December 19 | "Ue kara Mariko" | AKB48 | |
| December 26 | "We Never Give Up!" | Kis-My-Ft2 | |