The posts - which provide support for head teachers - were controversially cut in most schools as part of budget saving measures in 2013.
Education officials said the move had a negative impact on school performance levels.
Members of the education committee agreed to reappoint principal teachers from August.
It was described as "untenable" that head teachers had to cope with additional pressures.
Moray councillors have agreed to reappoint principal teachers in a number of primary schools.