Detective Nakamura, known in some sources as Chief Nakamura, serves as the head of Metro City's police force. A consistent figure across several iterations of the story, his role is most prominently defined in the 1963 original anime, the 1980 series, and the original manga. In his capacity as police chief, he is the direct superior of Inspector Tawashi, but often takes to the field as his companion during investigations.

In terms of personality, Nakamura is characterized as a stark contrast to the more boisterous and impulsive Tawashi. He is a timid and small-statured man who possesses a calm, rational, and soft-spoken nature. This rational side makes him less prone to jumping to conclusions than his subordinate. However, his quiet demeanor often means he struggles to interject when Tawashi launches into an emotional rant, despite being the higher-ranking officer. His core motivation is a sincere dedication to justice, positioning him as a reliable ally to Astro Boy.

Nakamura's primary role in the story is to represent the official law enforcement of Metro City. His key relationship is his partnership with Inspector Tawashi; despite their personality clashes, they work as a duo to solve crimes. While Tawashi may be the more vocal and energetic detective, Nakamura provides a steadying influence and holds the authority that can reign in his partner's excesses. As an ally to the protagonist, Nakamura represents the human authority figures who recognize Astro Boy's value and work alongside him to protect the city and combat discrimination against robots. Information regarding his personal background before becoming police chief is not detailed in the common sources. Similarly, he is not noted for possessing any remarkable physical or investigative abilities beyond those of a skilled and rational detective, and there is no documented outline of a significant personal character arc or development that he undergoes across the series.