Matsuyo Matsuno is the mother of the six Matsuno brothers and wife of Matsuzo Matsuno. She appears across various adaptations, from the original *Osomatsu-kun* to its sequel *Osomatsu-san*, consistently maintaining core traits while adapting to different narratives.

Physically, Matsuyo is tall and slender, typically depicted in a long-sleeved top, skirt, and apron. Her appearance evolves: in *Osomatsu-kun*, she sports short black hair flipped upward at the back with similarly styled bangs; by *Osomatsu-san*, her middle-aged design features hair pulled back into a bun, emphasizing a conventional housewife look. She consistently wears large round glasses, being severely nearsighted without them, to the point of failing to recognize large animals like gorillas or lions.

Her personality centers on being a no-nonsense, hardworking figure dedicated to managing her large family. She maintains energetic diligence despite childcare burdens, household expenses, and food demands. Early in *Osomatsu-kun*, her practical solutions include buying identical clothing in bulk for her sons, inadvertently making them harder to distinguish. Frustration with the family's size sometimes leads her to seek adoption opportunities for some sons to alleviate responsibilities.

Beneath this pragmatic exterior, Matsuyo exhibits a mischievous and crafty streak. She orchestrates schemes like ordering Osomatsu to scare his father in a bear suit or exploiting Iyami's insurance to deliberately break dishes. Alternate-universe stories explicitly link her sons' chaotic behavior to her influence. She also displays a fondness for gold and jewelry, pursuing them with opportunistic zeal, especially in scenarios imagining wealth.

Despite her resilience, she occasionally assumes a sympathetic role, such as being ignored when ill, forgotten during outings, or consumed by grief when a child leaves home. She reacts fiercely to those mocking her children's disappearances, blending maternal protectiveness with practicality.

In *Osomatsu-san*, Matsuyo confronts her adult sons remaining as NEETs at home. While retaining love and maternal instincts—sometimes babying them—her primary frustrations center on their unemployment and reluctance to move out. She expresses a strong desire for grandchildren, underscoring her wish for their transition into responsible adulthood.

Her background lacks extensive elaboration. An early manga chapter initially assigned the family the surname "Yamano" before settling on "Matsuno." Her given name, "Matsuyo," was rarely used in original serializations, mentioned only once by friends in the chapter *A Wreck of a Class Meeting*.