Jotaro Honma is a skillful surgeon who operated on Black Jack twenty-one years ago when the incident happened. He inspires Black Jack to study medicine and became a master surgeon himself.
He was a kind old man determined to save his patients no matter what or how low the chances of their survial. His determination and kindness inspired Black Jack to become a doctor himself.
Jotaro is the surgeon who operated on Black Jack and saved his life. Because of this incident, Black Jack was inspired to become a surgeon just like him and studied medicine soon after. During the surgery, he accidentally made a big mistake by leaving a scalpel under Black Jack's liver and only realizes it when one of the nurses informed that a scalpel was missing. Jotaro later felt guilty about this incident and was haunted by it, worrying that the scalpel pierced through any important organs.
Seven years later, he operated on Black Jack again, this time to remove the missing scalpel that is beautifully sheathed in calcium produced by Black Jack's body. Many years later, Black Jack visited a very ill and old Jotaro after receiving a package from him, containing the missing scalpel Jotaro extracted from him. During that time, he decided to take the opportunity and tells the story the package. After finishing his story, he lose consciousness and was rushed to a nearby hospital immediately. There, Black Jack decided to perform an operation on him but failed as Jotaro passed away due to old age. After his death, his daughter was taken care by Tetsu, the owner of Tom's Coffee Shop to repay for the operation he did on Tetsu before.
Jotaro has white sideburns, one on each side and a huge nose with small bumps on it. He is quite short, compared to Black Jack. He is always seen wearing a white surgeon uniform with black trousers.