|Japanese name:||佐々冈 よし子|
|School:||Adamine Middle School|
|Grade:||First-year middle school|
|Debut:||Saki Achiga-hen, Chapter 1|
|Live-action actor:||Rin Shigihara|
Yoshiko Sasaoka is a supporting character of the Saki Achiga-hen episode of side-A anime and manga.
Yoshiko has short brown hair and brown eyes. She wears blue jeans and a white shirt with a grey jacket. She also wears an orange and white headband.
Yoshiko is a student at Adamine Middle School. She was a member of the Achiga children's mahjong club before it was disbanded. She is shown throughout the manga and anime cheering on the Achiga mahjong team with everyone from the old children's mahjong club.