The activation of clay from Keskin/Ankara was carried out with sulphuric acid by the “dry process” at varions acid dosages. The nitrogen surface areas were determined after outgas- sing the products in vacuum at 160°C for 2 hours. Therefore, the change of surface area with the acid dosage by the activation has been obtained. It was observed that the surface area inc- reases with increasing acid percentage of acid and clay mixture up to 30% and then decreases rapidly to lower values. Maximum surface area was found to be 262 m2/g upon activation with 30% sulphuric acid.