Another soldier was killed and 15 others wounded, including a brigade general, when a helicopter bringing reinforcements to the combat zone crashed accidentally, according to the statement.
Five PKK fighters were also killed in clashes with Turkish security forces in the towns of Semdinli and Sirnak, near the Iraqi border, the military said.
Turkish planes have been regularly bombing PKK hideouts across the border in northern Iraq since an October 3 attack against a Turkish border outpost that killed 17 soldiers.
The PKK, listed as a terrorist group by Ankara and much of the international community, took up arms for Kurdish self-rule in the southeast in 1984, sparking a conflict that has claimed at least 44,000 lives.
Turkish officials estimate about 2,000 PKK fighters are residing in the mountains of northern Iraq, where they allegedly enjoy freedom of movement and can obtain weapons and explosives to stage attacks in Turkey.