The Post Primary Teachers' Association is seeking a 4% pay rise for its members, despite government plans to cut millions of dollars from the teaching pay roll.
Negotiations on the secondary teachers collective agreement are expected to start in July.
The PPTA's members have approved a claim seeking the pay rise, a maximum class size of 30 students and laptop computers for all secondary teachers.
The union says 97% of those who voted approved the claim.
The union estimates the pay rise alone would cost nearly $40 million, and the total cost of the claim would be nearly $105 million in its first year.
Last year the Government announced it would cut $45 million from the primary and secondary teacher payroll in the next financial year.
It has also called for restraint in public service pay rounds.
An advisory officer at the PPTA, Marion Norton, says that the planned cuts could have a severe impact on the pay talks and she hopes the Government will change its mind.