A Jiji Press survey conducted this month showed Thursday that 52.9% of respondents back the release into the sea of treated water from the meltdown-stricken Fukushima No. 1 nuclear power plant.
Of the overall respondents, 16.3% opposed the discharge of the water containing tritium, a radioactive substance, while 30.8% said neither.
Tokyo Electric Power Company Holdings, the operator of the Fukushima plant, started the water release on Aug. 24.
In a Jiji Press poll conducted in July, 39.2% backed the water release, while 28.0% were against it.
As the survey was conducted for four days through Monday, it does not reflect the Cabinet reshuffle on Wednesday.
A total of 47.9% of respondents were in favor of the government expanding and extending to the year-end its gasoline subsidy program, reflecting the public call for aid amid soaring gasoline prices brought on by rising crude oil prices and the yen's depreciation.
The figure exceeded the 33.8% who voiced their disapproval. A total of 18.3% were either indifferent or unsure.
On the government's way of handling a series of issues involving the country's My Number personal identification system so far, 54.6% expressed their displeasure, while 20.1% were in favor, and 25.3% were either in between or said that they did not know.
The interview-based survey covered 2,000 people aged 18 or over across the country. Of them, 60.0% gave valid responses.