The ban forbids any agricultural, forestry or debris burning from Sept. 22 through Oct. 29, said Board of Supervisors President Wayne Stokes.
Like many parts of Northeast Mississippi, Pontotoc County has been plagued with wildfires for weeks.
Late summer and early fall are typically the driest time of the year in the region, but much higher than usual temperatures have exacerbated the danger.
Rainfall in the region is about 1.3 inches below normal for the month, and temperatures in the region have been in the high 90s and even in triple digits over the last few weeks.
According to the Mississippi Forestry Commission, Pontotoc County is the third county in the state to have such a ban in effect.
Chickasaw County has banned outdoor fires through Oct. 31 with exceptions for Forestry Commission personnel and other certified burn managers; Lauderdale County has a complete burn ban in place through Oct. 4.