The Hasegawa Machiko Memorial Museum was built just across the street from the Hasegawa Machiko Art Museum as its annex. The two-story building consists of two permanent exhibition halls, a hall for planned exhibitions, a shop and a café.

The permanent exhibition hall on the first floor, “Machiko’s Works,” is dedicated to the artist’s manga with focus on her three major works: Sazae-san, Ijiwaru basan (“Granny Mischief”), and Epuron obasan (“Aunt Apron”). The other permanent exhibition hall, “Machiko’s Life,” showcases valuable materials that cast light on the character and work of the artist from her birth until her death at the age of 72.

Sazae-san was first published in 1946, the year after the end of World War II. At the time, Machiko was 26 years old. Later on, the author would reveal that she contemplated the plot of the manga during her walks on the beach outside her home in Fukuoka, where she was evacuated during the war, and that is why the names of all characters were derived from sea creatures. For instance, the name of the characters, such as Katsuo literally means “bonito,” and the name of his sister, Wakame, means “seaweed.” Later, together with her two sisters, Machiko started a publishing company, and released Sazae-san as a standalone manga book. She published Epuron obasan (“Aunt Apron”) and Ijiwaru basan (“Granny Mischief”) as serialized comic strips in weekly magazines, and expanded her activities as the popularity of Sazae-san grew. Despite the success of her works, however, it appears that Machiko also suffered greatly. After over-exerting herself, she developed an aversion to manga and stopped drawing altogether for an entire year. The ceramic works she created during that period are also displayed in the museum.

On the second floor of the museum there is a hall for planned exhibitions, where the works and paintings of Machiko Hasegawa are presented in a variety of thematic displays.