Hirai Miyo was born on December 11, 1999 in Tokyo, Japan
On December 3, during the BEYOOOOONDS Ouen Kikaku FC Event 2018 ~Fuyu no Jin ZIN~ at Yamano Hall, Hirai was revealed alongside Kobayashi Honoka and Satoyoshi Utano as the three winners of the Hello! Project "ONLY YOU" Audition. They would be part of BEYOOOOONDS together with CHICA#TETSU and Ame no Mori Kawa Umi.
On December 11, Hirai celebrated her 20th birthday in a fanclub event titled BEYOOOOONDS Hirai Miyo Birthday Event 2019, featuring two shows at LANDMARK HALL.
On January 24, Hirai was announced as the leader of SeasoningS.
She has an older sister.
- Name: Hirai Miyo (平井美葉)
- Nickname: Miyo-chan (みよちゃん), Miyo~n (みよ〜ん)
- Birthdate: December 11, 1999
- Birthplace: Tokyo, Japan
- Blood Type: A
- Height: 157 cm (5 ft 1.8 in)?
- Western Zodiac: Sagittarius
- Eastern Zodiac: Rabbit
- Hello! Project Status:
- UP-FRONT PROMOTION Status:
- 2018-12-03: Member
- BEYOOOOOONDS / SeasoningS Member Color: Purple
- Hello! Project Groups:
- Other Groups:
- See also: List:Hirai Miyo Discography Featured In
-  Boat
- [2020.04.25] BEYOOOOONDS / Ame no Mori Kawa Umi Kiyono Momohime・BEYOOOOONDS Hirai Miyo Birthday Event 2019
- [2021.05.xx] BEYOOOOONDS / Ame no Mori Kawa Umi Kiyono Momohime・BEYOOOOONDS Hirai Miyo Birthday Event 2020
-  Fushigi no Kuni no Alicetachi
-  Reborn ~13nin no Tamashii wa Kami-sama no Yume wo Miru~
-  Arabeyooooonds Nights
-  Nemureru Mori no Biyo
- [2018–2019] The Girls Live
- [2019–2020] AI・DOL PROJECT (AI・DOL プロジェクト)
- [2019–2020] Hello Pro! TOKYO Sanpo (ハロプロ!TOKYO散歩)
-  KURAGAE ~Watashitachi no Koto, Oshite Kudasai!~ (KURAGAE –私たちのこと、推してください！-)
- [2020–] Uta-navi! (うたなび！)
-  Hello! Project presents... "Solo Fes!"
-  Hello! Project presents... "Solo Fes! 2"
-  Shoujotachi no Ketsudan ~Micchaku!! Hello! Project 20 Shuunen Audition~ (AbemaTV)
- [2018–] Hello! Project Station
- [2018–] Upcoming
- [2019–] tiny tiny
- [2019–] OMAKE CHANNEL
- [2019–2020] Hello Pro Dance Gakuen
- [2019–2020] Hello Pro no Oshigoto Challenge
-  Hello Pro Kouhaku Taiko THE☆BATTLE 2019
- She has learned 14 years of classical ballet and half a year of both jazz and contemporary dance under a teacher. She also took hip hop for half a year when she entered university.
- She did not truly enjoy dancing until she was in middle school, when she discovered Sugawara Koharu and was impressed by her dancing.
- She became a fan of Takarazuka in 2007 after watching a TV broadcast of the Flower Troupe's Grand Romance "Akechi Kogorou no Jikenbo ― Kurotokage" ~Edogawa Rampo Saku "Kurotokage" Yori~ and TUXEDO JAZZ performances.
- Her favorite Takarazuka show is "Wakaki Hi no Uta wa Wasureji".
- She is interested in writing lyrics and song composition.
- She applied to the Takarazuka Music School at one point.
- She became a fan of Hello! Project after her older sister showed her music videos. Her desire to become a performer and her admiration of Hello! Project idols for their high skills led to her taking the audition.
- Gallery:Hirai Miyo
- List:Hirai Miyo Discography Featured In
- List:Hirai Miyo Concert & Event Appearances
- List:Hirai Miyo Pocket Morning Weekly Q&A
Oldest Member of SeasoningS
Leader of Seasonings
- "シューティングを超えるアイドル「ハロプロ2.0」BEYOOOOONDSインタビュー（３）" (in Japanese). ENTAME next. 2019-04-18.
- Shoujotachi no Ketsudan ~Micchaku!! Hello! Project 20 Shuunen Audition~ Episode #1. AbemaTV. 2017-11-13.
- "BEYOOOOONDS 加入メンバー決定！" (in Japanese). Hello! Project. 2018-12-03.
- "新グループ、グループ名決定のお知らせ" (in Japanese). Hello! Project. 2018-10-19.
- Hirai Miyo. "広島2日目〜harmony〜！そして昨日は憧れのダンス部！ 平井美葉" (in Japanese). BEYOOOOONDS Official Blog. 2019-07-14.
- "3人へのお知らせ【BEYOOOOONDS】" (in Japanese). BEYOOOOONDS Official YouTube Channel. 2021-01-24.
- Nishida Shiori. "12人のBEYOOOOONDS！西田汐里" (in Japanese). BEYOOOOONDS / CHICA#TETSU Official Blog. 2018-12-03.
- Shimakura Rika. "はぴば♡島倉りか" (in Japanese). BEYOOOOONDS / CHICA#TETSU Official Blog. 2018-12-11.
- Eguchi Saya. "♡スキップるんるん♡江口紗耶" (in Japanese). BEYOOOOONDS / CHICA#TETSU Official Blog. 2018-12-19.
- Yamazaki Yuhane. "ʚ 新しい仲間 ɞ 山﨑夢羽" (in Japanese). BEYOOOOONDS / Ame no Mori Kawa Umi Official Blog. 2019-01-04.
- "BEYOOOOONDS FCイベント2018 ~冬の陣ZIN ~" (in Japanese). Suzuki Keita Official Blog. 2018-12-03.
- Nishida Shiori. "尊敬する先輩。西田汐里" (in Japanese). BEYOOOOONDS / CHICA#TETSU Official Blog. 2018-12-13.
- Hirai Miyo. "踊ること。平井美葉" (in Japanese). BEYOOOOONDS Official Blog. 2019-01-10.
- Hirai Miyo. "タカラヅカ！ 平井美葉" (in Japanese). BEYOOOOONDS Official Blog. 2019-01-22.