is an important zoonotic fungus that causes dermatophytosis in domestic animals and their owners. Domestic cats are the primary reservoir for . Antifungal drugs frequently produce adverse effects on the host animal, increasing the demand for novel alternative treatments derived from nature. We evaluated the antifungal activity of essential oil (CEO) and ethanolic extracts (CEE) against in planktonic and biofilm growth. Twelve clinical isolates of were identified in feline dermatophyte samples. Using GC-MS, 18 compounds were identified in CEO, with carvacrol being the major constituent. HPLC analysis of CEE revealed that it contained rosmarinic acid, apigenin, and caffeic acid. The planktonic growth of all isolates was inhibited by extracts. The minimum inhibitory concentration at which ≥50% of the isolates were inhibited (MIC) was 128 µg/mL (32-256 µg/mL) for both CEO and CEE. The MIC values of CEO and CEE were 128 and 256 µg/mL, respectively. CEO at MIC (128 µg/mL) and 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of weak, moderate, and strong biofilm-producing . CEE at 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of all isolates. Overall, extracts inhibited planktonic growth and exhibited a significant antibiofilm effect against . Thus, is a potential source of natural antifungal compounds.