Tomohiro Kato, who killed seven people in a bloody stabbing spree in Tokyo's neon-lit Akihabara electronics district almost three years ago, was sentenced to death on Thursday.
The Tokyo District Court handed down the verdict to the 28-year-old former temporary auto plant worker who had told the court he was "fully responsible" for the attacks in which he also wounded 10 others.
Kato was arrested on the spot shortly after the noon-time attacks, in which he rammed a rented two-tonne truck into a public holiday crowd of pedestrians before getting out and randomly stabbing people with a double-edged knife.
"The defendant used a knife to attack those who just happened to be there and took the lives of many people who were completely innocent," said presiding judge Hiroaki Murayama, according to broadcaster NHK and news agencies.
"It was a brutal crime that did not indicate a shred of humanity on the part of the defendant. I have no choice but to sentence him to death."
Kato, dressed in a black suit and white shirt, was motionless as he listened to the sentence being read out.
The attacks shocked the world and Japan, which has a low violent crime rate, while throwing the spotlight on the online bullying that led up to the attacks in Akihabara, a centre for the manga comic and anime film subculture.
In one of the court hearings, Kato said he went on the rampage on June 8, 2008, because he had been the target of online bullying.
"I wanted people to know that I seriously wanted to stop the harassment on the Internet bulletin board that I used," he said, according to Japanese media.
Japan had had not seen such a deadly attack since seven years earlier to the day when a former mental patient stabbed to death eight children at an elementary school.
After the 2008 rampage, Japan banned possession of double-edged knives with blades longer than 5.5 centimetres (about two inches), punishable by up to three years in prison or a 500,000 yen fine.