Essential oils (EOs) are complex mixtures of low molecular weight compounds isolated from several plant families, mainly obtained by steam distillation and other simple techniques. The major components that provide the characteristic fragrance and biological properties to EOs are terpenoids and phenylpropanoid derivatives from mevalonic and shikimic acid pathway, respectively. They have been used by different medical traditional systems to treat a large number of diseases related to infections since ancient times. Many pharmaceutical and biological activities like, antibacterial, antifungal, anticancer, antimutagenic, antidiabetic, antiviral, anti-inflammatory, and antiprotozoal properties are assigned to them. Chemical characterization of EOs is extremely important since they often exhibit variations in their composition depending on different factors like plant variety, nutrition, application of fertilizers, climate, geographic location, seasonal variations, etc. The current status of human diseases produced by fungi, as well as a deep revision of drugs used to treat them and trends in the pharmaceutical industry for searching new antifungal drugs, are covered in this chapter. EOs as antifungal agents against human pathogens have also been discussed as alternative to drugs clinically used nowadays. We also provide the mechanism of antifungal action of these natural products.Fil: Di Liberto, Melina Gabriela. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Svetaz, Laura Andrea. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Castelli, Maria Victoria. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rai, Mahendra. Sant Gadge Baba Amravati University; IndiaFil: Derita, Marcos Gabriel. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin