On July 7, Fukuda was announced as one of the winners of the Hello! Project "Juice=Juice" "Tsubaki Factory" Goudou Shin Member Audition audition and would join Tsubaki Factory alongside Kasai Yuumi, Yagi Shiori, and Yofu Runo.
She has an older sister and an older brother.
As of April 2021, Fukuda is currently in her second year of high school.
The following list are notable friendships Yofu Runo has acquired:
Her mother named her after the English word "Marine".
Here is a list of nicknames that was used to refer to Fukuda Marine:
- Marine (まりん)
- Maririn (まりりん)
- Name: Fukuda Marine (福田真琳)
- Nicknames: Marine (まりん), Maririn (まりりん)
- Birthdate: October 18, 2004
- Birthplace: Shanghai, China
- Raised: Nagasaki, Japan
- Blood Type: AB
- Western Zodiac: Libra
- Eastern Zodiac: Monkey
- Hello! Project Status:
- 2021-07-07: Tsubaki Factory member
- UP-FRONT PROMOTION Status:
- 2021-07-07: Member
- Tsubaki Factory Member Color: Royal Blue
- Hello! Project Groups:
- Tsubaki Factory (2021-present)
- She was born in Shanghai, China and she lived there until the second year of elementary school.
- She is the first member in Hello! Project history to be from the Nagasaki Prefecture.
- She has the same birthday as Juice=Juice member Irie Risa.
- She shares the same surname as 1st generation ANGERME member Fukuda Kanon, and 1st generation Morning Musume member Fukuda Asuka.
- She always admired Tsubaki Factory and was happy to join them.
- Her audition number was 147.
- Her favorite character are Cinnamon and Sirotan.
- Her childhood dream was to become an ice skater.
- Her favorite animal is the quokka.
- Her favorite English Songs which she learned from her mom are "Top of the World" by The Carpenters and "I Want You Back" by Jackson 5.
- Gallery:Fukuda Marine
- List:Fukuda Marine Discography Featured In
- List:Fukuda Marine Concert & Event Appearances
- List:Fukuda Marine Publications Featured In
- List:Fukuda Marine Pocket Morning Weekly Q&A
- "好きなキャラクター 福田真琳" (in Japanese). Tsubaki Factory Official Blog. 2021/07/24
- "「Juice=Juice」「つばきファクトリー」 新メンバー決定！" (in Japanese). Hello! Project. 2021-07-07
- "好きな英語の曲 福田真琳" (in Japanese). Tsubaki Factory Official Blog. 2021-09-01