Jiro Shima is a minor but significant character in the Space Battleship Yamato narrative, primarily known for being the younger brother of Daisuke Shima, the chief navigator and helmsman of the Yamato. Born in the year 2192, his given name, Jiro, carries the meaning of "second son," reflecting his position in the family. In early development drafts of the story by creator Leiji Matsumoto, the character who would become Daisuke Shima was initially envisioned under the name Jiro Daisuke, showing a connection between the name Jiro and the navigator role from the concept phase.

Within the story, Jiro Shima is depicted as a young boy who remains on Earth during the Yamato's historic voyage to Iscandar and its subsequent battles. His primary role is to represent the loved ones left behind, providing a grounded, emotional perspective from the home planet. A key scene illustrates his relationship with his brother, where the two share a rare, playful moment together, often involving a soccer ball. In this interaction, Daisuke Shima works to reassure his younger brother that the Yamato's mission will succeed and that he will be safe, a promise that carries significant dramatic weight given the dangers of the journey.

Jiro's personality is defined by his unwavering confidence and faith in the Yamato's crew and his older brother. Despite the immense public doubt and fear that grips Earth's population as they face an existential threat, Jiro remains steadfast in his belief that the spaceship will save the world. This hope, centered on his family member at the helm, serves as an emotional anchor, highlighting the personal stakes of the crew's mission for their families back home. He is motivated by the simple but powerful desire for his brother's safe return and the salvation of Earth.

Jiro Shima also appears in later installments of the original series, notably in the 1983 film Space Battleship Yamato: Final Chapter, where he is a confirmed character. His presence in this final chapter continues to connect the legacy of the original Yamato crew to the next generation. His most significant relationship is with his brother, Daisuke Shima, and by extension, the entire Yamato crew in whom he places his trust. As a young character, his development is not a primary focus of the narrative, but his journey is one of maintaining hope and resilience in the face of overwhelming adversity on Earth. In terms of notable abilities, Jiro does not possess any combat or tactical skills; his primary depicted talent is playing soccer, a detail used to characterize him as an ordinary, spirited child in the scene he shares with his brother.