Japan hanged two men on Thursday, bringing to eight the number of prisoners executed since the conservative government of Shinzo Abe came to power a year ago.
"There are various criticisms of the death penalty... but Japanese law allows for it and I believe we have people's support in principle," Justice Minister Sadakazu Tanigaki said as he announced the latest executions.
Apart from the United States, Japan is the only major industrialised democracy to use capital punishment.
Surveys have showed the death penalty has overwhelming public support despite repeated protests from European governments and human rights groups.
One of those executed Thursday was Ryoji Kagayama, 63, who stabbed to death a student from China after robbing her in 2000. He also knifed a man to death in 2008 in a failed robbery attempt.
The other prisoner was Akira Morinaga, 55, who drowned a relative of his former wife in a bath in 1986 and murdered an acquaintance of her days later.
Japan now has 129 inmates on death row, according to justice ministry data.
Amnesty International Japan blasted the executions, saying "the high-paced executions under the Abe administration stands squarely against repeated international calls for abolition of death penalty."
Tokyo did not execute anyone in 2011, the first full year in nearly two decades without an execution amid muted debate on the rights and wrongs of a policy that enjoys wide public support.
But in March last year it abruptly resumed its use of capital punishment, dispatching three multiple murderers.
Seven prisoners were executed in 2012.
International advocacy groups say the system is cruel because inmates can wait for their executions for many years in solitary confinement and are only told of their impending death a few hours ahead of time.