Susan Lambert has been a sharp critic of the Liberal government, continually accusing the Liberals of underfunding education and violating teacher's rights.
In a new release announcing she'll step down at the end of the 2013 school year, Lambert says teachers feel a responsibility more than ever to speak out for a quality public education system.
She says no matter which party is in government, the union must press for better teaching and learning conditions that meet the diverse needs of students.
Lambert's successor will be chosen at the Federation's annual meeting in Vancouver, which begins Saturday.
The convention will also discuss education funding, collective bargaining and political action it may take during the provincial election campaign in May.