Kazuko Hosoki (細木 数子 Hosoki Kazuko?, born 4 April 1938, Tokyo) is a Japanese fortune teller, as well as the author of over 100 books. Hosoki appeared frequently on the original Iron Chef, where she would serve as one of the four celebrity judges that would determine the outcome of each match.
She is often seen stating her opinions very strongly on Japanese TV shows. Some of her views may be taken as conservative. She has repeatedly made very traditionalist statements on women in the family, stating that a woman's main function should be to support her husband's career. She has also publicly endorsed prime-minister Junichiro Koizumi's controversial visits to Yasukuni Shrine.
Sumo wrestling yokozuna (grand champion) Asashōryū is a close friend of Hosoki. Asashōryū is superstitious and has sought Hosoki's advice and predictions. They have appeared together on TV specials and once Asashōryū rented her white Rolls-Royce. She maintains a residence in Arashiyama, Kyoto City.