Species: Goldfish (Human-faced fish) → Mermaid → Human Real Name: Brunhilde Gender: Female Age: 5 years old Family: (Mother) Gran Mammaré, (Father) Fujimoto, younger sisters The eldest daughter of Fujimoto and the sea goddess Gran Mammaré. A 5-year-old red human-faced fish with many younger sisters who look just like her. She has a very cute appearance in both her fish and human forms. Having inherited powerful magical abilities from her goddess mother, she demonstrates various spells such as healing Sosuke's wound by licking it or casting barriers. On land, she lives as a human, sporting a light pink bob cut and wearing a pink dress. She has a crush on Sosuke. She left the sea (ran away from home) and is currently living at Sosuke's house. Favorite food: Ham. She is not very good at speaking.

Species: Human Gender: Male Age: 5 years old Family: (Mother) Lisa, (Father) Koichi He lives with his mother, Lisa, in a two-to-three-story house on a cliff. His father, Koichi, is a ship captain and cannot come home often. He is a boy with an upright, honest, and pure heart. One day, he finds Ponyo stuck in a glass jar in the sea and rescues her. In the process, Ponyo licks the blood off his finger. He has brown hair, black eyes, and wears a yellow T-shirt with brown shorts. He is popular at kindergarten.

Species: Human Gender: Female Age: 25 years old Family: (Husband) Koichi, (Son) Sosuke Sosuke's mother. She works at a senior care facility called the Sunflower House, which is right next to Sosuke's daycare. She takes care of Ponyo as if she were her own child. She makes warm soup and ramen with ham for them. When Ponyo falls asleep from exhaustion while eating ramen, she lays her down on the sofa. She has a bright, refreshing personality, a kind demeanor, and a beautiful appearance. She has short brown hair and wears a navy shirt with white trousers. She drives aggressively (Sosuke is already used to her driving style).

Species: Human → Unknown Gender: Male Age: Unknown (Adult) Family: (Wife) Gran Mammaré, (Eldest Daughter) Ponyo, Ponyo's younger sisters A wizard with mysterious powers who knows how to create marine life. He travels in a submarine called the Basking Shark to live under the sea. He has long, light pink hair, and his daughter Ponyo inherited his messy hair. He dislikes and loathes humans. He is not very good at handling children (...) Though he is overbearing, his love for his children seems genuine. He is currently searching for Ponyo, who ran away from home.

Species: Goddess Gender: Female Age: Unknown Family: (Husband) Fujimoto, (Eldest Daughter) Ponyo, Ponyo's younger sisters Unlike her husband, who is hostile toward humans and worried about Ponyo, she shows a broad-minded side by understanding Ponyo's feelings and wanting to pair her with Sosuke. She can change her size at will. Her true form radiates the aura of a massive, mysterious deity, but she shrinks to the size of a normal human when talking to Fujimoto or inside a barrier. However, she remains very tall. Unlike Ponyo and Fujimoto, who have messy curls, she has voluminous, beautiful wave-like hair that glows with an aura, and its color tone is much more vibrant. She always uses polite speech with everyone but speaks informally to her children. She rarely reveals herself, making a sighting of her extremely rare.

They live in the sea and look like small goldfish (human-faced fish). They are cute. They sometimes help Ponyo and there are a vast number of them. They cannot speak well.