Accessory zircon is an important geochemical indicator of magma fertility in magmatic-hydrothermal deposits. It is used in ore deposit exploration due to the widely accepted consideration of the resistant zircon behavior during overprinting processes. The main purpose of present study is to investigate the geochemical characteristics of zircons in the high sulfidation epithermal deposit Chelopech deposit (Bulgaria) and test their stability in hydrothermal alteration zones of different intensity – from propylithic through sericitic and the most intensive advanced argillic. The zircon grains were selected from the main igneous rock type of the Sharlo Dere target – the diorite porphyries. In the different samples, the ore hosting diorite porphyries have undergone varying degrees of alteration. According to the combined LA-ICP-MS U-Pb age and trace element data, in advanced and even moderate argillic alteration zones some trace elements in the zircons reveal signs of mobility.