Interior Minister Ali Yerlikaya said eight police and another security force member were wounded in a raid on a property in the town of Yalova, on the Sea of Marmara coast south of Istanbul.
More than 100 addresses were raided nationwide early on Monday.
Turkey has stepped up operations against suspected IS militants in 2025, as the group returns to prominence globally.
The United States carried out a strike against the militants in northwest Nigeria last week, while two gunmen who attacked a Hanukkah event at Sydney's Bondi Beach in December appeared to be inspired by Islamic State.
On December 19, the US military launched large-scale strikes against dozens of IS targets in Syria in retaliation for an attack on American personnel.
Police raided the house in Yalova on the suspicion that militants were hiding there overnight.
Sporadic gunfire was heard during the operation, which lasted nearly eight hours, according to a Reuters photographer at the scene.
Last week, Turkish police detained 115 suspected Islamic State members they said were planning to carry out attacks on Christmas and New Year celebrations in the country.
Yerlikaya told reporters the militants killed in Monday's attack were Turkish citizens, adding that five women and six children were brought out of the property alive.
In the past month, police arrested a total of 138 Islamic State suspects and carried out simultaneous operations on Monday morning at 108 different addresses in 15 provinces, he said.
Police had sealed off the road approaching the house in the early hours and smoke was visible rising from a nearby fire, while a police helicopter flew overhead.
The Istanbul chief prosecutor's office said last week that Islamic State militants were planning attacks against non-Muslims in particular.
Almost a decade ago, the jihadist group was blamed for a series of attacks on civilian targets in Turkey, including gun attacks on an Istanbul nightclub and the city's main airport, killing dozens of people.
Turkey was a key transit point for foreign fighters, including those of Islamic State, entering and leaving Syria during the war there.
Police have carried out regular operations against the group in subsequent years and there have been few attacks since the wave of violence between 2015 and 2017.
