As Steve outlines his plot to borrow a camcorder from Toshi in "Threat Levels", an older and heavier Mrs. Yoshida appears as Toshi sneaks it past her. This version appears again in "Phantom of the Telethon" as an audience member. She also cheers on Tank Bates at FedExField in "Daddy Queerest".
In "Weiner of Our Discontent", she speaks English as well as Akiko but Francine apparently pretends not to understand her, being upset that she chose her own brand of hot dogs for Steve and Toshi's hot dog eating contest; which was justified as the hot dogs Francine brought were poisonous.
Stan says that he couldn't understand Toshi's parents when he talked to them about making Toshi a man in "The Magnificent Steven".
She appears in a cameo at the end of "Shallow Vows" with Toshi.
Roger and Stan take their idea for "Male Stripper Shoes" to Mr. Yoshida to get funding for their idea in "National Treasure 4: Baby Franny: She's Doing Well: The Hole Story". He agrees to bankroll their idea on the condition that they kill his wife but they find they are unable to do it. They later spot an ad for their shoes and find he has stolen their idea.
Mrs. Yoshida's determination to get Akiko and Toshi into a good college forces a confrontation with Steve and Francine in "Spelling Bee My Baby".
After a short time in simulated woods in "I Ain’t No Holodeck Boy", Toshi claims he can no longer remember his mother's face.
Hiko Yoshida is voiced by Sandra Oh.
- "Threat Levels" (early draft)
- "The Magnificent Steven" (mentioned)
- "Phantom of the Telethon" (early draft)
- "Weiner of Our Discontent"
- "Daddy Queerest" (early draft)
- "Shallow Vows"
- "May the Best Stan Win"
- "National Treasure 4: Baby Franny: She's Doing Well: The Hole Story"
- "Spelling Bee My Baby"
- "The Missing Kink"
- "I Ain’t No Holodeck Boy" (mentioned)