Crays Hill primary, near Billericay, has been losing around 50 children a year since around 500 Travellers moved into the village over the past three years.
Just 52 pupils will be in the school next term - almost 40 will be Traveller children. Only a dozen village families have said they will send their children to the school.
Nine of the 10 non-teaching governors resigned last week in what they said was a row over school funding. Sarah Gallagher, headteacher, resigned in February and leaves in July.
David McPherson-Davis, chairman of Crays Hill parish council, is one of the governors who quit. He said: "Many of the Travellers' children are illiterate when they enter the school and need extra support. They get this at the expense of the other pupils. Their parents have decided to cut their losses and are leaving."
Mrs Gallagher said falling rolls have led to budget cuts which could mean her working up to half her week as a teacher. "I wanted to be a non-teaching head," she said.
Essex county council said the school would remain open - a new governing body has been appointed and a new head would be recruited.
Councillor Iris Pummell, cabinet member for education, said: "There is adequate funding for this school which currently has funding in reserve."