Naoko Yoshioka is the mother of Haru Yoshioka in The Cat Returns. She is a calm and balanced woman who maintains a warm and affectionate relationship with her daughter. Despite Haru's occasionally chaotic and impulsive nature, Naoko responds with gentle humor and enjoys teasing her lightheartedly. Her personality is even-tempered and supportive, providing a stable presence in Haru's daily life.

The primary source of stress in Naoko's life is her work, which can sometimes cause her to become distracted and lose focus on her surroundings. This tendency leads her to miss certain events, such as Haru not coming home from school on the day her adventures in the Cat Kingdom begin. Nevertheless, Naoko's role in the story is grounded in the human world. She is the one who recalls and shares with Haru the childhood memory that Haru once claimed to have talked to a white cat, a revelation that subtly validates Haru's unusual experiences and hints at her long-suppressed ability to communicate with cats.

Naoko's key relationship is with her daughter. She acts as a reassuring link to Haru's ordinary life and family history. She does not undergo major character development in the film, but her quiet, loving presence helps frame Haru's journey as one of self-discovery that begins in a recognizable, caring home. She has no supernatural abilities; her notable trait is her nurturing patience and the lighthearted bond she shares with Haru.