Project owner Fennovoima said 76.5 % of residents in Pyhäjoki, northern Finland, support the plant, which is scheduled to begin commercial operation in 2028.
When surrounding municipalities were also taken into account, 71.1% of residents were in favour of the project, an increase of 3.9 percentage points over a similar survey last year.
Hanhkivi-1 will be a 1,200-MW VVER pressurised water reactor. The reference plant for the unit is Leningrad 2 in Sosnovy Bor, Russia.
Fennovoima said the increased support is an indication that the impact of the project on the local economies is becoming more visible.