The Guyana Teachers Union (GTU) says its members will embark upon strike action from August 27 to ensure a wage agreement is reached with the Ministry of Education.
In a memo to teachers, GTU President Mark Lyte said the strike will continue until further notice.
Schools are due to re-open for the new academic term on September 3.
The union has asked principals to return school keys to Education Departments on Friday.
The union is also asking teachers not to report for work from the commencement of pre-term activities.
Last week, Mr. Lyte said the long-running pay dispute with government might be headed for arbitration.
The GTU is insisting on a multi-year agreement from 2016 to 2019.