Yuki (ゆきちゃん) is the mother of Hamtaro. She appeared in a photo, and in the sky as a spirit, in the 3000 Hammy Steps in Search of Mommy OVA. According to Hamtaro, she is "a white and fluffy wonderful mommy". Her spirit told Hamtaro that as long as he is with his friends, she will always be with him too.
- In the English Happy Birthday Hamtaro Special!, Yuki's entire role is cut, presumably due to her part in the story (her death) being deemed too dark for the US audience.
- In Hamutaro's Tottoko Picture Book Dechu, Yuki is shown to have a full litter of about a dozen babies. In the anime, however, it appears that Hamtaro is her only child.
- It is unknown what is the cause of her death, she likely died of an old age.
- It is unknown who her mate is making Hamtaro's father unknown.
- Main article: Yuki/Gallery