The effect of the oregano extract (Origanum vulgare L.) on the growth of Fusarium and Penicillium species isolated from cakes and ready-for-use fresh salads from different kinds of vegetables was investigated. Contents of the active component of extract were identified by GC-MS and they include: carvacrol (34.2%), carvone (18.5%), p-cimene (8.05%), thymol (3.74%). The oregano extract showed the ability to reduce mould growth at all applied concentrations. Stronger inhibitory effect on the growth of Penicillium species, contrary to Fusarium, was determined. At extract concentration of 2.5 mL/100 mL, growth of P. aurantiogriseum, P. glabrum and P. brevicompactum was completely inhibited during 14 days of incubation. At the same concentration, growth of Fusarium proliferatum was inhibited by 81.71%, F. oxysporum by 85.84%, F. verticillioides by 86.50%, P. chrysogenum by 86.2% and F. subglutinans by 88.85%.