Abstract Essential oil of Chloroxylon swietenia was studied for its antifungal potential against clinically isolated fungal strains as well as the cytotoxic effect on Vero cells. The essential oil was analyzed by gas chromatography (GC) and GCâmass spectrometry (GCâMS). Antifungal activity was studied by disc diffusion method and serial broth dilution method. The toxicity of the essential oil was evaluated in normal Vero cell line by MTT assay. The GC and GCâMS analyses revealed that the essential oil contained 36 compounds and the major chemical compounds were germacrene-D (22.4%) followed by limonene (17.3%) and geijerene (15.4%). The antifungal assay showed that Candida albicans was the most sensitive fungal strain tested, with the strongest mean inhibition zone (22.0±1.32 mm) followed by C. parapsilosis (21.5±1.32 mm). The results of the minimum inhibitory concentration (MIC) indicated that the oil inhibited all the fungal strains tested at the highest concentration of 125 μg/mL. Toxicity on normal Vero cell line showed the IC50 value of 115.47 μg/mL. The results obtained in the present study will certainly be helpful in future clinical trials to validate its use as a phytotherapeutic product. Key words: antifungal activity Aspergillus Candida Chloroxylon swietenia cytotoxicityessential oil Acknowledgements We thank Dr. R. Panneerselvam, Professor and Head, Department of Botany, Annamalai University for having provided the laboratory facilities. One of the authors (A. Senthilkumar) is grateful to Indian Council of Medical Research, New Delhi, India for the award of Senior Research Fellowship (Award No. 45/39/2009/BMS/TRM).