The essential oil of Munnozia senecionidis Benth. (Asteraceae), obtained by hydrodistillation, was analyzed by GC-MS. Twenty compounds were identified, accounting for 93.9% of the oil. The most abundant components were caryophyllene oxide (19.9%), trans-nerolidol (12.1%), epi-alpha-cadinol (9.4%) and hexadecanoic acid (8.8%).