|Birthdate||September 20, 1997|
|Birthplace||Nara City, Nara, Japan|
|Current Age||26 Years Old|
|Social Networks||7gogo / Instagram / SHOWROOM / TikTok / Twitter/ Fanclub|
|Idol Career Info|
|Debuted||April 2014 / Team 8|
- 1 Catchphrase
- 2 Trivia
- 3 History
- 4 AKB48 Senbatsu Elections
- 5 Team History
- 6 Singles Participation
- 7 Albums Participation
- 8 Units
- 8.1 Stage Units
- 8.2 Concert Units
- 8.2.1 Team 8 National Tour 〜47 no Suteki na Machi e〜
- 8.2.2 Kojimatsuri ～Kojima Haruna Kanshasai～
- 8.2.3 AKB48 Group Seijin Shiki Concert ~Otona ni Nanka Naru Mono ka~
- 8.2.4 AKB48 Group Kanshasai ~Rank in Concert~ (Senbatsu Sousenkyo Rank-in (17th-100th) members performance)
- 8.2.5 8gatsu 8nichi wa Eito no Hi Natsu da! Eito da! Pitto Matsuri 2018
- 8.2.6 AKB48 Team 4 Tandoku Concert 〜Tomodachi ga Dekita〜
- 8.2.7 AKB48 Team 8 Cuties Concert 〜We are!! Cuties!〜
- 8.2.8 AKB48 Zenkoku Tour 2019 ～Tanoshii bakari ga AKB!～
- 8.2.9 AKB48 Tandoku Concert 2021 〜Suki Naraba, Suki da to Iou~
- 8.2.10 August 8th is Eito no Hi 2022 Puroland no Suteki na Machi e
- 8.2.11 MX Matsuri! AKB48 60th Single "Hisashiburi no Lipgloss" Announcement Commemoration Concert in Budokan 2022
- 8.2.12 Okada Nana Congratulation concert ~Thanks infinite~
- 8.2.13 AKB48 Current Team Final Concert 2023 in KT Zepp Yokohama 〜To Be Continued〜
- 8.2.14 MX Matsuri AKB48 62nd Single "Idol Nanka Janakattara" Release Commemoration Concert
- 9 Photobooks
- 10 Media Appearances
- 11 Gallery
- いきなりですが質問です。みなさんの好きな色は何ですか?（○○）でもでも、やっぱりそこは?（桃色） 奈良県から来ました大西桃香、高校2年生の26歳です
- Ikinari desu ga shitsumon desu. Mina-san no suki na iro wa nani desuka? (○○) Demo demo, yappari soko wa? (Momoka) Nara-ken kara kimashita Onishi Momoka, 26-sai desu
- (I have a sudden question. What is everyone's favorite color? (○○) But but, of course it's? (Peach colored!). From Nara Prefecture, 26-year-old Onishi Momoka)
- Team 8 Performances: Tokushima, Nagano, Okinawa, Hyogo
- Hobbies: Dancing, listening to music
- Favorite food: Omurice made by her mother
- Least favorite food: Tomatoes and cherry tomatoes
- Admired members: Oshima Yuko, Okada Nana
- Favorite song: Naminori Kakigoori
- Favorite AKB48 stage song: Keibetsu Shiteita Aijou
- Special skills: Hula hoop, massages
- Future ambition: To be an indispensable presence in AKB48
- Message to the fans: I will do the best I can in order to grant everyone smiles and excitement, so I am under your care!!
- She is very close with her mother.
- Her father passed away in 2015, one year after she joined AKB48.
- She is a longtime fan of idols, including AKB48. She said she was inspired to audition for AKB48 after the 2012 Tokyo Dome Team Shuffle. Seeing members like Miyazawa Sae and Takajo Aki be transferred to SNH48 and JKT48 had led Momoka's friends to say they had "no idea what was going on with AKB48 anymore", and AKB48's popularity began to decline. Momoka saw this, and as a fan, she was disappointed. She auditioned for AKB48 in hopes of showing the good points of the group to the world.
- She describes her personality as "like a cat". Theater manager Hosoi Takahiro said she is a hard worker with a reserved and mild-mannered personality.
- She was appointed as a Nara City Tourism Ambassador on November 19th, 2017 by the Nara City mayor.
- She is known for her popular daily SHOWROOM streams, that earned her the Center position on the SHOWROOM Senbatsu in 2019.
- As a prize, she was chosen as the cover model for a women's travel pamphlet in Cebu Island, Phillipines.
- In October 2020 she had four teeth removed and false teeth put in. This has affected her pronunciation when speaking.
- She loves the video game Splatoon.
- On October 10th, 2023, she announced her graduation from AKB48. October 10th was her late father's birthday.
- In April, joined AKB48 as a member of Team 8.
- On August 5th, had her theater debut for Team 8's 1st stage, PARTY ga Hajimaru yo.
- On August 27th, was part of her first song, 47 no Suteki na Machi e, on AKB48's 37th single Kokoro no Placard.
- On December 23rd, had her concert debut at Team 8's 1st national tour, Team 8 National Tour 〜47 no Suteki na Machi e〜 2015.
- On November 7th and 8th, was one of the 12 selected Team 8 members that performed on Cool Japan Festival at Manila, Philippines.
- On February 20th, had her first appearance on AKBINGO!.
- On February 28th, was part of the shonichi performance for AKB48's 6th special stage, Minerva yo, Kaze wo Okosen.
- On March 15th, was part of her first senbatsu for AKB48's 47th single Shoot Sign.
- On December 8th, during the AKB48 12th Anniversary Shuffle, received a concurrent position with Murayama Team 4.
- On June 6th, was part of the shonichi performance for the revival of Team 4's 2nd stage, Te wo Tsunaginagara.
- On June 16th, at the 10th Senbatsu Sousenkyo, ranked for the first time at #38.
- On August 6th, had her final appearance on AKBINGO!.
- On February 2nd, she appeared at the Japan Expo 2020 in Thailand.
- On December 8th, at the AKB48 16th Anniversary Team Shuffle, it was announced her kennin position with Team 4 would be removed and replaced with Taguchi Team K instead.
- On February 9th, had her first appearance on AKB48, Saikin Kiita? ~Issho ni Nanka Yatte Mimasen ka?~ (AKB48、最近聞いた？～一緒になんかやってみませんか？～).
- On April 4th, was part of the senshuuraku performance for Team 4's Te wo Tsunaginagara stage.
- On April 19th, officially became a member of Taguchi Team K.
- On April 27th, had her final appearance on AKB48, Saikin Kiita? ~Issho ni Nanka Yatte Mimasen ka?~ (AKB48、最近聞いた？～一緒になんかやってみませんか？～).
- On August 3rd, had her first appearance on AKB48, Saikin Kiita Kamo? ~Issho ni Nanka Yatte Mimasen ka?~ AKB48、最近聞いたかも？～一緒になんかやってみませんか？～).
- On September 14th, had her final appearance on AKB48, Saikin Kiita Kamo? ~Issho ni Nanka Yatte Mimasen ka?~ (AKB48、最近聞いたかも？～一緒になんかやってみませんか？～).
- On October 7th, had her first appearance on AKB48 Sayonara Mouri-san (AKB48サヨナラ毛利さん).
- On April 20th, appeared on a special program by ReHacQ- (リハック−) for YKK promotion called "Business Request Meeting" (ビジネスクリエイティブ会議), together with Oguri Yui.
- On April 30th, fully transferred to Team K.
- On October 10, announced her graduation.
- On October 17, transferred to AKB48 Regular Members after the disbandment of Team K.
AKB48 Senbatsu Elections
- 6th Senbatsu Election - Not Ranked
- 7th Senbatsu Election - Not Ranked
- 8th Senbatsu Election - Not Ranked
- 9th Senbatsu Election - Not Ranked
- 10th Senbatsu Election - #38 (Next Girls)
- Team 8 → Team 8 and Team 4 → Team 8 and Team K → Team K → Regular Members
- Joined AKB48 as a Team 8 member on April 3, 2014
- Had a Concurrent Position in AKB48's Team 4 from December 8, 2017 (AKB48 12th Anniversary Shuffle) to April 19, 2022
- Had a Concurrent Position in AKB48's Team K from April 19, 2022 (Announcement: December 8, 2021 (AKB48 16th Anniversary Team Shuffle)) to April 30, 2023
- Fully transferred to Team K on April 30, 2023 (Announcement: October 7, 2022)
- Transferred to Regular Members on October 17, 2023
- Shoot Sign
- Ne mo Ha mo Rumor
- Moto Kare desu
- Hisashiburi no Lip Gloss
- Doushitemo Kimi ga Suki da
- Idol Nanka Janakattara
- Henachoko Support (Koko ga Rhodes da, Koko de tobe!)
- Issho no Aida ni Nannin to Deaerudarou (0 to 1 no Aida)
- Namida ni Shizumu Taiyou
- Rudolph the Red-Nosed Reindeer
AKB48 Group Kanshasai ~Rank in Concert~ (Senbatsu Sousenkyo Rank-in (17th-100th) members performance)
- Amai Kokansetsu (Solo with backing dancers)
- Kiseki wa Ma ni Awanai (Center)
MX Matsuri! AKB48 60th Single "Hisashiburi no Lipgloss" Announcement Commemoration Concert in Budokan 2022
- New Team Concert
- Day 3
- Day 1
- Day 2
- Day 3
- AKBINGO! (2017 - 2019)
- AKB48, Saikin Kiita? ~Issho ni Nanka Yatte Mimasen ka?~ (AKB48、最近聞いた？～一緒になんかやってみませんか？～) (2022)
- AKB48, Saikin Kiita Kamo? ~Issho ni Nanka Yatte Mimasen ka?~ AKB48、最近聞いたかも？～一緒になんかやってみませんか？～) (2022)
- AKB48 Sayonara Mouri-san (AKB48サヨナラ毛利さん) (2022 - 2023)
Onishi Momoka (2019)
Onishi Momoka (July 2018 - Team 8)
Onishi Momoka 10th Senbatsu Election Poster (2018)
Onishi Momoka (2018) (AKB48)
Onishi Momoka (July 2017)
Onishi Momoka 9th Senbatsu Election Poster (2017)
Onishi Momoka (2017) (AKB48)
Onishi Momoka (2016)
Onishi Momoka (2016) (AKB48)
Onishi Momoka (2016)
Onishi Momoka (2015)
Onishi Momoka (2014)
Onishi Momoka (2014)
Onishi Momoka (2014)