The Fiji Sugar and General Workers' Union says two thirds of members that are sugar mill workers have voted to take strike action.
The union leadership says the workers earn below the poverty line, with wages declining by 40 percent in real terms in the past seven years.
It says when it held secret ballots of workers last week the Fiji Sugar Corporation threatened workers while soldiers and police were at all polling stations, sometimes interfering in the voting process.
The union says, despite this intimidation, it has a strong endorsement for industrial action and will now consider how to proceed.
Last week, the Corporation agreed to give workers a rise of 5.3 percent.
Also last week the attorney general, Aiyaz Sayed-Khaiyum accused the general secretary of the union, Felix Anthony, of abusing his power in a vain attempt to survive at a time when his relevance in the economy has become questionable.
Mr Anthony says he will not respond to personal attacks but rather talk about what are straight forward issues concerning the plight of the sugar mill workers.