In a letter to members, Mr McAvoy attacks delegates to the annual conference in Blackpool at Easter who voted for strike action.
"Conference resolutions were agreed calling for strikes or undefined industrial action on almost every issue debated . . . Those who promoted them saw them as a means for a political attack on the Government," the letter says. "Conference also agreed to support all organised opposition to racism and fascism, whether violent nor non-violent."
Mr McAvoy said those who voted for strikes and violent demonstrations were representing members who do not share their political perspective at conference, where union policy is decided. He said he now plans regular surveys and ballots of the whole membership on a full range of issues.
The first test will be a ballot, decided for at conference, for a one-day strike in summer term over class size. The ballot papers were sent out this week and the result is expected on June 9. Mr McAvoy has made it clear that he does not support the strike.
The letter was immediately attacked by a group of left-wing executive members, including Carole Regan, the NUT's vice-president. They accuse Mr McAvoy of being out of step with the union.
"It is 20 years and more since he was last a teacher. He is paid a salary way beyond the aspirations of classroom teachers and therefore completely out of touch with members," they said.