This is the fifth ballot in 15 months
ASTI members have voted to reject the ‘Outcome of Talks’ proposals on Junior Cycle reform and pay.
In a ballot of the union’s 18,300 members, members voted by 52.5% to 47.5% to reject the proposals from the Department of Education.
The turnout in the ballot was 75%.
ASTI President Ed Byrne said: “Despite the implementation of punitive measures for ASTI members and threats of further measures, ASTI members are standing up for their most vulnerable colleagues and for their students.”
Mr Byrne said teachers who are members of the ASTI have made “a difficult but courageous decision”.
“This ballot has taken place in the context of strong mandates for the continuation of our industrial action campaigns up to strike action.
“In the space of 15 months we have balloted our members on five separate occasions.
“ Our members are standing firm and telling us to continue to hold the line on Junior Cycle reform and to vigorously pursue equal pay for equal work for our young teachers,” he added.
The ASTI’s Standing Committee will meet next week to consider the outcome of the ballot.
In a statement following the ballot, Education Minister Richard Bruton said: "I am disappointed with the outcome of ASTI’s ballot on the comprehensive proposals put forward by the Teachers’ Conciliation Council.
"It is regrettable that many ASTI members will now suffer permanent financial losses and loss of other benefits as a result of this choice.
"As I have stated previously, the proposals represented the final outcome of the process and there will be no further offer made to ASTI.
"I want to reassure students and parents that the new Junior Cycle programme is proceeding in schools.
"Implementation plans are not impacted by the outcome of this ballot.
"Schools have been notified of a second calendar window in the 2016/17 school year to allow for the completion and submission of the Junior Cycle English Assessment Task by students who were prevented from meeting the initial deadline.
"The interests, rights and wellbeing of students must be paramount."