At the beginning of the series, Shinichi is already well-known as a brilliant young detective, the "Savior of the police force", for solving many difficult cases the professionals could not. He is extremely intelligent, and even from a young age was very intuitive and observant. Due to the influence of his father and the general laissez-faire environment at home, he has long been an incessant and persistent reader, especially of mystery novels. His father, Yusaku started taking Shinichi to crime scenes as a child, which inspired him to be a detective. Due to his bluntness and matter-of-fact manner, Shinichi can come off as rude and arrogant. However, he cares deeply about human life, unable to understand how any reason could be sufficient motive for murder, and is convinced that driving a culprit to suicide is no better than murder itself. The few times he has been too late to save a life haunt him throughout the series.
Prior to his transformation, Shinichi enjoyed being in the spotlight, reveling in making local headlines and receiving fan-mail, and still has a flair for the dramatic like his mother that can be seen every time he sets out a deduction in pieces building to a climax. Throughout the series, Shinichi's predicament forces him to gain a sense of humility.
Despite his popularity with the masses and his schoolmates, he has very few close friends. As Shinichi he was close to Ran and Agasa, and after deaging he befriended Heiji, Haibara, and to some extent the other Detective Boys. Despite his intelligence, Shinichi is rather dense when it comes to 爱情 或者 romantic subjects, though perhaps not to the same extent as Heiji Hattori.