Miwa Sado, 31, logged 159 hours of overtime in the month before she died in 2013 at Japan's NHK broadcaster.
Following an investigation, NHK revealed this week the 31-year-old political journalist died from heart failure from working excessive hours, according to CNN.
In Japan, death due to overwork is known as 'Karoshi' and is considered a social issue.
NHK said it was taking its reporter’s death seriously and is looking to change the way journalists work.
Japanese businesses have a history of squeezing the most out of employees due to relaxed labour laws.
The nation does not have legal restrictions on working hours and activists have pushed for years for the government to enforce safer laws. Prime Minister Shinzo Abe is also pushing to improve working conditions.
Some white-collar workers or Japanese ‘salaryman’ have been documented to clock up to 13 hour days for six days a week.
The suicide of a worker at an advertising agency made national headlines when it was previously linked to overwork.
Matsuri Takahasi was found to have clocked 105 hours of overtime in the month leading up to her death.
Japanese regulators found the extreme work schedule resulted in her suicide, according to CNN.