Mari Matsuzawa is a Japanese manga artist and original creator, known for her work in the comedy and romance genres, particularly for the series Recently, My Sister Is Unusual. She is a female creator from Saitama Prefecture, Japan. Before establishing her career as a manga artist, Matsuzawa worked in the animation industry at the studio SHIN-EI Animation, where she held the position of animation checker. This background in anime production would later inform her involvement in the adaptation of her own works.

Matsuzawa's career as a manga author began in the early 2000s. Her early works include the series Hinadori Girl (also known as Machine Girl), which was serialized in Monthly Comic Gao! and published in three compiled volumes. She also worked on the manga adaptation of the light novel series Inukami!, written by Mizuhito Akiyama, which was serialized in the same magazine and collected in six volumes. Other notable manga from this period include Sanbun no Ichi, serialized in Manga Time Kirara Forward, and Doken, a one-volume web comic.

Matsuzawa is best known as the original creator of the manga Recently, My Sister Is Unusual. The series was serialized in Monthly Dragon Age from December 2010 to June 2016 and compiled into eleven volumes. The manga was adapted into a television anime that aired from January to March 2014, for which Matsuzawa received credit as the original creator and also contributed to the original character designs. A live-action film adaptation was released in 2014, and an original animation DVD was also produced. The story follows a girl possessed by a spirit who must fall in love with her step-brother to ascend to heaven, a premise that incorporates supernatural elements into a romantic comedy about a newly formed family.

Following the conclusion of her most famous work, Matsuzawa continued to create manga. She authored Fukuneko, a series about fortune-bringing cats, which was serialized in Monthly Action from 2016 to 2018 and collected in four volumes. As of 2019, she began serializing a new series titled Miharashiso no 5-nin no Hanayome in Monthly Comic Dengeki Daioh.

Beyond her own serialized works, Matsuzawa has contributed to anthology collections for numerous popular series, illustrating stories within the worlds of titles such as The Familiar of Zero, Inukami!, The Mystic Archives of Dantalian, The Devil Is a Part-Timer!, and Made in Abyss. This body of work establishes Mari Matsuzawa as a creator who transitioned from the animation industry to a successful career in manga, achieving mainstream recognition through a work that blended risqué comedy with supernatural romance, and who remains active as a contributor to both her own series and shared anthology projects.