Wataru Yoshizumi (吉住渉) is a Japanese mangaka. She was born as Mari Nakai (中井 真里, Nakai Mari) on June 18, 1963 in Tokyo, Japan. She graduated with a degree in economics from Hitotsubashi University.

Yoshizumi started her career as a mangaka while working as an office lady. Her debut manga was a yomikiri (short story) called "Radical Romance" that was published in 1984, in the summer issue of Ribon Original. She is known as a social mangaka, and is a good friend of fellow mangakas Naoko Takeuchi, Ai Yazawa, Miho Obana, and Megumi Mizusawa.

Yoshizumi currently (as of 2007) has her works published in both Ribon and Chorus.