The last survivor of the Ghost Tribe, possessing immense power even among yokai. He usually lives a peaceful life in the GeGeGe Forest with his father, Medama-oyaji. While he tries to avoid involvement with the human world as much as possible, he will head there with the clattering of his geta whenever a letter reporting a yokai-related incident reaches the Yokai Post.

A cat yokai and one of Kitaro's companions. She hides a high combat ability that belies her beautiful appearance. When the greedy Nezumi-otoko causes trouble, her eyes change color and she transforms into a feral state to attack. She usually acts cool and aloof toward everyone.

A yokai in the form of an old man. He lures enemies with the cry of a baby and then crushes them by turning his body into a heavy stone. He loves alcohol and is constantly being scolded by Sunakake-baba for being drunk.

A yokai in the form of an old woman. She freely manipulates sand imbued with special spiritual power. She can attack enemies and heal the stamina of allies. She is a motherly figure relied upon by Kitaro and the others, caring for both yokai and humans alike, and is surprisingly tech-savvy with modern digital devices.

A first-year middle school girl. She is exceptionally curious and finds herself drawn to Kitaro and his friends who live in a world different from humans. While Kitaro sometimes sees her as a meddler, her sudden inspirations often provide the key to solving cases.

A yokai of the Ghost Tribe. Though he once lost his life to a severe illness, his strong feelings for Kitaro, who was still a baby, allowed him to be reborn as an eyeball yokai. As Kitaro's biological father, he watches over him warmly and provides accurate advice. He usually enjoys various types of tea-bowl baths prepared by Kitaro. He is very knowledgeable about yokai matters.

A subordinate of Backbeard.

A yokai made of a long strip of white cloth. He flies through the air with his long, slender body and sometimes carries Kitaro on his back. A yokai from Kyushu who loves girls; he immediately tries to woo any girl he sees.

The supreme emperor of Western yokai, boasting overwhelming spiritual power. He is a dictator whose goal is to rule the entire world. He invaded Japan with his subordinates in pursuit of Agnes, a witch who fled after stealing the Ring of Arcana.

A subordinate of Backbeard.