The antifungal properties of some commercial plant waters obtained as side products in producing distilled oils were investigated. Paper disc samples were impregnated with various plant waters and exposed to wood decay fungi for 3 months in Petri dishes. Ten types of plant water (Laurus nobilis, Calluna vulgaris, Lavandula stoechas, Thymus vulgaris, Myrtus communis, Eucalyptus globulus, Mentha pulegium, Urtica dioica, Melissa officinalis, and Matricaria chamomilla were examined. Seven fungi were used (Phanerochaete chrysosporium, Ceriporiopsis subvermisphora, Gloeophyllum trabeum, Trametes versicolor, Oligoporus placenta, Pleurotus ostreatus, and Coniophora puteana). The antifungal activities of the plant waters obtained from thyme and lavender were particularly high.