The comparative lichenoindication research of air quality in the parks of Lviv, in Novoyavorivsk and its outskirts, and in the neighbourhood of the lake Sinevir natural-protected area of the Carpathians on the base of epiphytic lichenoflora of deciduous and coniferous trees was conducted. The method of determination of izotoxic lichen zones is offered after the Index of Atmospheric Purity and characteristic species of lichens for the deciduous (Quercus robur, Betula pendula, species of genera Populus and Acer) and the coniferous (Pinus sylvestris, Picea abies) trees. Key words: Lichenoindication, pollution of air, Lviv, Yavoriv district, Carpathian, deciduous and coniferous trees.