Police seized 150 kilograms (330 pounds) of explosives, detonation equipment and two Kalashnikovs, the report said, with Turkey on high alert after the New Year Istanbul nightclub attack claimed by ISIS.
As per report, IS leaders in northern Syria had ordered members to carry out a "sensational" attack in Turkey.
Police seized the explosives and Kalashnikovs, along with the equipment for making suicide bombs, devices for setting bombs off via mobile phone, a pistol and cartridges. The stash had been buried under the earth in an open area and was found by sniffer dogs after the suspects were questioned.
The operation came just over a month after 39 people, mainly foreigners, were killed on New Year's Eve when a gunman went on the rampage inside a plush Istanbul nightclub.
The massacre claim was taken by IS, its first clear claim for a major attack in Turkey, although it was blamed for several bombings in 2016.
Last weekend security forces detained over 750 people suspected of IS links in Turkey's biggest ever crackdown against the group.
The western allies of Turkey have been accusing it for long for not doing enough to stop the flow of jihadists across its borders and emergence of IS cells in its own cities, including Gaziantep.