K/Ar analyses were carried out on unaltered samples of volcanic rocks from the Gutai Mts., of Romania. The analysed samples, collected from the surface locations from the whole area represent lava flows. According to the previously performed geological mapping and existing lithostratigraphic relationships, the volcanic activity in the area developed during Badenian–Dacian time, (Borcos et al. 1973), with several eruption phases. Most of the volcanic rocks were considered Pontian and post-Pontian in age with a probable extension towards the Pliocene time (Borcos et al. 1973; Lang 1975). The newly obtained apparent ages range between 9–14 Ma printing out the andesitic volcanism in the Gutai Mts., started at the Badenian–Sarmatian boundary and unquestionably continued until the Upper Pannonian.