The soldiers were attacked while on patrol in Hakkari province on the road between Hakkari city and the town of Cukurca, Dogan news agency reported.
Eight soldiers were also wounded in the attack close to the border with northern Iraq, the agency said.
Turkish security forces were engaged in a large-scale military operation in Hakkari to target Kurdish militants in the area earlier this month.
Attacks against Turkish military personnel intensified since the collapse of a two-and-a-half-year ceasefire last July, resulting in the deaths of hundreds of security forces.
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Activists claim that innocent civilians have also been caught up in the renewed conflict.
Nearly 40,000 people have been killed since the PKK insurgency began in 1984.
The group is proscribed as a terrorist organisation by Turkey as well as by the European Union and the United States.