Other cult members hanged on Friday included scientists who helped produce the sarin in an Aum laboratory, the cult's "intelligence" director, a member responsible for capturing potential cult defectors, and the cult's director for acquiring land.
The followers of the Aum Shinrikyo cult were also accused of several other murders and an earlier sarin attack in Matsumoto in 1994, which killed eight and injured 600 people. "I offer my apologies to the victims and their families, and I feel more strongly than ever that we must work to prevent a recurrence". He had been on death row for over a decade for the attack that killed 13 people and injured thousands more.
Aleph, a successor group to Aum Shinrikyo, is still involved in a court case over settlements to the victims of the 1995 and other attacks.
Shoko Asahara was one of 13 cult members waiting for the final result of pending verdicts and is the first to be executed by hanging for the 1995 attack, as well as the murder of the Sakamoto family and production of a chemical weapon.
Another six members of the cult are still on death row.
The group went on developing their chemical weapons, and on March 20, 1995 released sarin at several points across the Tokyo subway during the morning rush hour.
"When I think of those who died because of them, it was a pity (my husband's) parents and my parents could not hear the news of this execution", she said.
The attack shocked Japan, a country that prided itself on low crime rates and social cohesion. Five were executed for their role in Tokyo subway attack, while another was executed for his role in the group's other crimes.
"Justice demands accountability but also respect for everyone's human rights".
In Asahara's eight-year trial, he spoke incoherently and never explained the motive for the attacks or acknowledged responsibility.
Aum "predicted the end of the world and the final decisive battle of good and evil, and planned to eradicate enemies in various ways such as (by using) poison gas", Tass news agency said, adding, "That is prohibited all over the world, including in Russian Federation".
In 1984, Asahara founded Aum Shinrikyo as a spiritual group which mixed Hindu and Buddhist beliefs.
In 1990, Asahara and a group of followers ran unsuccessfully for parliamentary election, and after the failed bid he became increasingly violent.
More than 20 years of trials involving Aum members came to an end in January 2018 when Japan's supreme court upheld the life sentence of Katsuya Takahashi.
Aum Shinrikyo is designated a terrorist organisation in the U.S. and many other countries, but Aleph and Hikari no Wa are both legal in Japan, although designated as "dangerous religions" subject to surveillance.
His execution was delayed due to ongoing cases against his co-conspirators, the last of whom was arrested in 2012.