Makoto Sei Watanabe (born 1952) is a Japanese architect living in Tokyo.

Makoto Sei Watanabe was born in Yokohama, Japan.

He worked under Arata Isozaki in Tokyo until starting his own firm, the Makoto Sei Watanabe Architectural Office, in 1984.

[1] Watanabe's designs are characterized by a modern approach, using computers and mathematical algorithms to generate his styles.

He is also the subject of Makoto Sei Watanabe: Conceiving the City, published by l'Arca Edizioni in 1999.