Turkish air force jets destroyed scores of caves and shelters used by the PKK in northern Iraq early on Wednesday.
The air operation took place in the Zap and Avasin-Basyan regions between midnight and 1:30 am (2100-2230 GMT), Turkey's military said.
It did not provide information on potential casualties.
The operation in northern Iraq came as Turkey opened an army base in the country's southeastern area called the "Devil's Triangle," where the borders of Turkey, Iraq and Iran meet.
The Hakkari army base is nearly 3,000 metres above sea level. Turkey aims to shut down PKK hideouts, passages, and weapons smuggling in the area.
More than 1,200 people, including security force personnel and civilians, have lost their lives since the PKK – listed as a terrorist organisation by Turkey, the US and the EU – resumed its decades-old armed campaign in July 2015.
Iraq to continue hitting Daesh
Meanwhile, Iraqi Prime Minister Haider al-Abadi on Wednesday said Iraq will continue hitting Daesh targets in Syria, as well as in neighbouring countries, if they give approval.
"I respect the sovereignty of states, and I have secured the approval of Syria to strike positions in its territory," he told a conference in the Iraqi Kurdish city of Sulaimaniya.
Abadi on February 24 announced the first Iraqi air strike inside Syrian territory, targeting Daesh positions in retaliation for bomb attacks in Baghdad.
I will not hesitate to strike the positions of the terrorists in the neighbouring countries, we will keep on fighting them - Iraqi Prime Minister Haider al-Abadi
Iraqi forces are also fighting Daesh in northern and western Iraq. Currently, an operation is underway in Mosul to drive the terrorist organisation from Iraq's second biggest city and its last major stronghold in the country.
In mid-February, Iraqi forces backed, by a US-led air coalition, began the operation as part of a wider campaign launched last October to retake the entire city.
Daesh took control of Mosul, along with much of northern and western Iraq, in mid-2014, after which it declared a "caliphate" in areas of Iraq and Syria it had occupied.