- Name: Yamagishi Riko (山岸理子)
- Nickname: Rikoriko (りこりこ)
- Birthday: November 24, 1998
- Birthplace: Chiba, Japan
- Blood type: B
- Height: 155cm
- Specialty: Badminton, dance, cartwheels, playing the recorder
- Hobby: Reading, collecting pens, going to the movies alone, listening to music
- Favorite Color: Lime green, pink
- Looks Up To: Suzuki Airi, °C-ute
- Hello! Project groups:
Yamagishi Riko was introduced as a member of Hello! Pro Kenshuusei at the "Hello Pro Kenshuusei Happyoukai 2012 ~6gatsu no Nama Tamago Show!~" concert on June 17, 2012. She went on to participate in the "Morning Musume 11th Generation ~Suppin Utahime~" audition, but failed.
On April 29, 2015 she was revealed to be one of six members in a new group, named Tsubaki Factory. The unit consisted entirely of Hello! Pro Kenshuusei, including Ogata Risa, Niinuma Kisora, Tanimoto Ami, Kishimoto Yumeno, and Asakura Kiki.
- [2017.04.27] Riko (理子)
- TV Programs
-  Hello Pro Kenshuusei no Tadaima Kenshuuchuu! (ハロプロ研修生のただ今研修中!)
- [2014–2015] UP-FRONT CHANNEL Recommend
- [2015–] Hello! Station (ハロ！ステ)
-  Nettai Danshi (熱帯男子)
-  Bokutachi Karen na Shounen Gasshoudan (僕たち可憐な少年合唱団)
-  Kurukuru to Shi to Shitto (くるくると死と嫉妬)
-  Thank You Very Berry (サンク ユー ベリー ベリー)
-  Kizetsu Suruhodo Aishiteru! (気絶するほど愛してる!)
-  Zoku 11-nin Iru! Higashi no Chihei, Nishi no Towa (続・11人いる!東の地平・西の永遠)
-  Nega Poji Poji (ネガポジポジ)
- Her favorite sport is badminton.
- Her favorite season is winter.
- Favorite flower is lavender.
- Favorite food is wakame egg soup.
- Her favorite Hello! Project songs are "Hatsukoi Cider" by Buono!, "Bagel ni Ham & Cheese", "GamushaLIFE", "Bishoujo Shinri", and "Wakaretakunai..." by °C-ute, "Shin Nippon no Susume!" by S/mileage, and "KEEP ON Joshou Shikou!!" by Juice=Juice.
- Wrote in a magazine that her dream is to be an idol that sings both cute and cool songs.
- Her motto is "Everyone is different, but that's what makes everyone good."
- Her favorite music genres are hip hop, R&B, and J-Pop.