A record 42 defendants were sentenced to death in 2004.
The number of death sentences this year, up by 12 from 2003, is the highest since courts started taking data in 1980, according to a Kyodo News survey based on court data.
Sixty-eight death-row inmates did not appeal their sentences or had lost appeals as of Wednesday, the survey found.
The figures reflect moves to impose severer sentences amid increases in the number of heinous crimes.
Courts also tend to give tough penalties in consideration of the feelings of crime victims and their families.
A group of lawmakers failed to submit a set of bills to the Diet to abolish executions and introduce life imprisonment in place of the death penalty, largely as a result of this trend.
District courts sentenced 14 people to death in 2004, while high courts handed down death penalties on 15 people. The Supreme Court sentenced 13 to death, its first double-digit figure since 1980.
The 42 include Aum Shinrikyo founder Shoko Asahara and five other former members of the cult.