US President Barack Obama will be among the world leaders arriving in city on Turkey's southern coast for the summit on 15-16 November.
Two of the suspects arrested on Friday are said to be Russian.
Turkey has stepped up operations against IS militants following a string of deadly bombings.
Anti-terror police carried out simultaneous raids in three districts of Antalya early on Friday, local media said.
Officers reportedly seized "digital materials" during the operation.
How dangerous is Turkey's unrest?
Turkey v Islamic State v the Kurds
Violence has escalated in Turkey since a suicide bombing in July by suspected IS militants.
The attack near the border with Syria killed more than 30 Kurds.
The IS group was also blamed for twin blasts that killed more than 100 people in Ankara last month.
The latest crackdown comes after Sunday's election, in which President Recep Tayyip Erdogan's ruling AK Party regained the parliamentary majority it lost in June.
Mr Erdogan has vowed to press ahead with operations against all "terrorists" including Islamic State and the outlawed rebel Kurdistan Workers' Party (PKK).
The conflict in Syria and the fight against IS are expected to be on the agenda at the G20 summit, which will be held in a seaside resort just outside Antalya.
Turkish police have arrested 20 people suspected of links to the Islamic State group in Antalya a week before the city hosts a G20 summit, reports say.