In 2009, Miyazaki Rio joined UP-FRONT KANSAI after passing an audition.
In 2010, Miyazaki became a member of the idol group Pizza♥Yah!.
In 2013, Miyazaki formed a three-member group named Lovelys!!!! with the duo Yes Happy! as a result of their joint lives together. Miyazaki became the leader of Lovelys!!!! and subsequently left Pizza♥Yah!, but continued her solo career while Yes Happy! also pursued their own activities.
After Yagi Saki joined Lovelys!!!! as a fourth member in June 2014, Miyazaki gradually decreased her solo activities to focus on the group.
On July 20, it was reported that Miyazaki Rio had been diagnosed with COVID-19. She had reported symptoms of fever and sore throat since the day before, and took a PCR test which had a positive result. She will concentrate on her treatment under the direction of health centers and medical institutions. Yagi Saki and various staff members had been determined to be close contacts, but have no symptoms and tested negative by PCR test. On July 29, it was announced that she had been cleared to return to activities on July 30 by the discretion of health centers and medical institutions, as she had completed her treatment.
- Name: Miyazaki Rio (宮崎梨緒)
- Nickname: Riitan (りーたん)
- Birthdate: August 26, 1994
- Birthplace: Osaka, Japan
- Blood Type: A
- Height: 151 cm (4 ft 11.4 in)?
- Western Zodiac: Virgo
- Eastern Zodiac: Dog
- Lovelys Member Color:
- Pizza♥Yah! (2010-2013)
- Lovelys (2013-)
- [2014.04.14] candy pop love / Tulip (candy pop love/チューリップ)
-  Harukanaru Toki no Naka de 6 Gaiden ~Tasogare no Kamen~ (daily guest role)
- She likes western music, especially Michael Jackson.
- She loves singing and dancing and would like to try acting.
- She has the same last name as former Juice=Juice leader Miyazaki Yuka.