- Name: Michishige Sayumi (道重さゆみ)
- Nicknames: Sayumin (さゆみん), Sayu (さゆ), Shigesan (しげさん), Oyakata (親方)
- Birthday: July 13, 1989
- Birthplace: Ube, Yamaguchi, Japan
- Blood Type A
- Skills: Braiding, Y-balance, math
- Hobbies: Collecting things (hair ties, stickers, collectible toys, erasers, etc.), talking
- Motto: Never refuse a gift.
- Favorite food: Mother's homemade mentaiko spaghetti, chocolate
- Favorite words: Thank you. Left-right symmetry.
- Favorite colors: Pink
- Hello! Project groups:
- Metro Rabbits H.P. (2006)
Michishige Sayumi was selected from the Morning Musume LOVE Audition 2002 to join Morning Musume as part of the sixth generation, along with Kamei Eri and Tanaka Reina. She made her debut with the single "Shabondama", was first featured on the Ai no Dai 6 Kan album, and made her first concert appearance at the Morning Musume Concert Tour 2003 Haru "Non Stop!" concert.
While considered the weakest of her generation vocally, she tries to compensate with good looks and a cute personality, openly referring to herself as the the cutest member of Morning Musume. She is sometimes considered the successor to Ishikawa Rika, given the role they have each played within the group.
In 2004, Michishige and Ishikawa together formed the ecological awareness unit EcoMoni, and every summer they appear at various environmental and cultural festivals. In 2005, they released a joint photobook titled "Angels".
She was a regular co-host, with Kamei Eri and Nakazawa Yuko, of the "Eric Kamezou no Maido Arii" segment of Hello! Morning. She was also the designated mentor of seventh generation member Kusumi Koharu.
She is currently hosting her own half-hour radio show, "Konya mo Usa-chan Peace", on CBC Radio every Tuesday at 11:30 PM.
Starting 2009, she's appeared several times on different Japanese variety TV shows, either on her own or along with other members, usually with Yaguchi Mari. On summer 2009 she gained a decent recognisement in the Japanese media due to her appearing in high-rating shows like London Hearts, Downtown DX and Odoru Sanma Gouten, as well as in less popular shows. A TV Guide article from August 2008 praised her sharp tongue. Michishige started using her sharp tongue since time ago, particularly in her radio show, where on certain episodes she commented on something from the point of view of "Good/Angel Sayumi" and "Bad/Black/Devil Sayumi".
She became the Leader of Morning Musume after the graduation of Niigaki Risa on May 18, 2012.
Michishige announced her intention to graduate from Morning Musume on April 29, 2014, to take place on the last day of the Fall 2014 tour on November 26, 2014 at Yokohama Arena. Following the graduation she took a hiatus lasting nearly two years, suddenly resuming activity on her blog on October 2, 2016. She slowly revealed her intention to return to the entertainment industry over the course of several blog posts making use of wordplay in the titles, officially announcing on November 26, 2016 that she would make her return the next year during Spring. She stated specific plans would be made public at a later date, while also confirming that she wanted to perform on stage again.
- [2017.04.10] SAYUMINGLANDOLL ~Saisei~ (SAYUMINGLANDOLL～再生～)
- [2007.07.18] 17 ~Love Hello! Michishige Sayumi DVD~
- [2008.10.01] LOVE STORY
- [2009.07.22] 20's time.
- [2010.04.28] Sayu
- [2011.03.31] homey
- [2013.01.16] Alo Hello! Morning Musume 6ki DVD (Michishige Sayumi, Tanaka Reina)
- [2014.11.19] SAYUMI+
- [2004.10.29] Michishige Sayumi (道重さゆみ)
- [2007.01.13] Doukei (憧憬)
- [2007.06.30] 17 ~Love Hello! Michishige Sayumi Photobook~ (17 ~ラブハロ!道重さゆみ写真集~)
- [2007.12.09] Sousou (蒼蒼)
- [2008.09.25] LOVE LETTER
- [2009.07.11] 20sai 7gatsu 13nichi (20歳7月13日)
- [2010.04.26] La
- [2011.10.27] Sayuminglandoll
- [2012.01.25] Mille-feuille (美ルフィーユ)
- [2013.10.27] Blue Rose
- [2014.10.26] YOUR LOVE
- [2003.07.16] Hello Hello! Morning Musume 6ki Members (ハロハロ! モーニング娘。6期メンバー写真集) (Kamei Eri, Michishige Sayumi, Tanaka Reina)
- [2005.11.16] Angels (エンジェルズ) (Ishikawa Rika, Michishige Sayumi)
- [2010.11.12] Hello Hello! ~Memories~ (ハロハロ！) (Kamei Eri, Michishige Sayumi, Tanaka Reina)
- [2013.09.30] Morning Musume 15th Anniversary Photobook ZERO (モーニング娘。 15th Anniversary Photobook ZERO) (Michishige Sayumi, Fukumura Mizuki, Ikuta Erina, Sayashi Riho, Suzuki Kanon, Iikubo Haruna, Ishida Ayumi, Sato Masaki, Kudo Haruka, Oda Sakura)
- [2014.05.30] Michishige Camera '13-'14 (ミチシゲカメラ'13-'14) (Michishige Sayumi, Fukumura Mizuki, Ikuta Erina, Sayashi Riho, Suzuki Kanon, Iikubo Haruna, Ishida Ayumi, Sato Masaki, Kudo Haruka, Oda Sakura)
- [2014.12.15] Alo Hello! Morning Musume '14 Photobook (アロハロ！ モーニング娘。'14写真集) (Michishige Sayumi, Fukumura Mizuki, Ikuta Erina, Sayashi Riho, Suzuki Kanon, Iikubo Haruna, Ishida Ayumi, Sato Masaki, Kudo Haruka, Oda Sakura)
- [2015.02.25] Michishige Camera 2~'14graduation~ (ミチシゲカメラ2~'14graduation~) (Michishige Sayumi, Fukumura Mizuki, Ikuta Erina, Sayashi Riho, Suzuki Kanon, Iikubo Haruna, Ishida Ayumi, Sato Masaki, Kudo Haruka, Oda Sakura)
- [2014.07.13] Sayu
-  Hoshizuna no Shima, Watashi no Shima ~Island Dreamin'~ (星砂の島、私の島 ~アイランド・ドリーミン~)
-  Tatakae!! Cyborg Shibata San (闘え!! サイボーグしばた3)
-  Keitai Deka THE MOVIE 3: Morning Musume Kyuushutsu Daisakusen! ~Pandora no Hako no Himitsu (ケータイ刑事 THE MOVIE3 モーニング娘。救出大作戦！～パンドラの箱の秘密)
- TV Programs
- [2003–2007] Hello! Morning (ハロー! モーニング)
-  Soreyuke! Gorokkies (それゆけ!ゴロッキーズ)
-  Futarigoto (二人ゴト)
- [2007–2008] Haromoni@ (ハロモニ@)
-  Berikyuu! (ベリキュー!)
- [2008–2009] Yorosen! (よろセン!)
- [2009–2010] Bijou Houdan (美女放談)
- [2010–2011] Aimai na! (あいまいナ!)
- [2010–2011] Bijo Gaku (美女学)
-  Zaki Kami! ~Zakiyama-san to Yukai na Nakamatachi~ (ザキ神っ！～ザキヤマさんとゆかいな仲間たち～)
- [2011–2012] HELLOPRO! TIME (ハロプロ！ＴＩＭＥ)
-  Ikinari Ougon Densetsu (いきなり黄金伝説) (In 10,000 Yen Challenge)
- [2012–2013] Hello! SATOYAMA Life (ハロー！ＳＡＴＯＹＡＭＡライフ)
- [2014–] The Girls Live
- TV Dramas
- Net Programs
-  Dai 10 Kai Hello Pro Video Chat (第10回ハロプロビデオチャット)
-  Hello Pro Hour (ハロプロアワー) (4 episodes)
-  Aozora Shower (青空シャワー)
-  Michishige Sayumi no "Mobekimasutte Nani??" (道重さゆみの『モベキマスってなに？？』) (Host)
- Net Dramas
-  Ribbon no Kishi The Musical (リッボンの騎士ザ・ミュージカル) (as Rue)
-  Cinderella The Musical (シンデレラ The ミュージカル) (as Fairy)
-  Ojigi de Shape Up! (おじぎでシェイプアップ!) (as Chii Ruruka)
-  Fashionable (ファッショナブル) (as Morinari Anna)
-  Idol Nihonryuu ~Onna Nichibu~ (アイドル日本流～おんな日舞～)
-  SAYUMINGLANDOLL~SAISEI~ (SAYUMINGLANDOLL~再生~)
- [2006–2014] Konya mo Usa-chan Peace (今夜もうさちゃんピース)
- [2007–2014] Young Town (ヤングタウン)
- Her official Morning Musume image color is pink.
- Has an older brother and older sister.
- Became close friends with Kamei Eri during their training camp.
- Is noted for not having changed her hair in terms of cut or color since she joined.
- Was the Morning Musume mentor of Kusumi Koharu.
- Her catchphrase is "Usa-chan Peace!" while holding two peace signs beside her head, like rabbit ears. It has also been used in place of the "Sexy Beam" during some performances of "Koi no Dance Site."
- She won an award for aerobics in elementary school, and also took piano lessons.
- Prior to joining Morning Musume, she most admired Takahashi Ai and Ishikawa Rika.
- Her father is a researcher for the chemical company Ube Industries.
- Noted her favorite Morning Musume song to be "Kare to Issho ni Omise ga Shitai!" in a 2012 magazine interview.
- Her cousin is Michishige Saho from Houkago Princess.