New K-Ar data from the Apuseni Mountains Neogene volcanic area are presented. When combined with geological and magnetic polarity data, the new data clarify the duration and evolution of this volcanic area. They show that the Neogene volcanic activity took place during the Late Badenian-Pannonian (15–7 Ma). The beginning of calc-alkaline andesitic volcanism (around 15–13 Ma) had an explosive character giving a widespread volcano-sedimentary formation. The volcanic activity reached the paroxysm during the Sarmatian (13.5–11 Ma), when thick lava flows and large volcanic structures were emplaced. This activity decreased in the Pannonian (10–7 Ma) and was restricted to the central and northeastern parts of the studied area. In the central part, the volcanic activity stopped in the Early Pannonian (10 Ma), while in the northeastern part it lasted until the Late Pannonian (7 Ma). The volcanic products are covered by pure sedimentary formations in only a few parts of the area. During all this time, tectonic activity played an important role in the basin’s development and volcanic processes.