The aim of the study is to determine the essential oil profile and antioxidant activity of endemic Marrubium parviflorum subsp. oligodon. The essential oil contents were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) using Solid Phase Microextraction (SPME). In addition, total phenolic content and the capacity of antioxidant activity measured by DPPH• and FRAP assays were determined. Twenty-three (64.12%) essential oil components were determined. Pentadecanolide was found to be the major essential oil and palmitic acid was determined as main fatty acid in Marrubium parviflorum subsp. oligodon. Total phenolic content was found to be 39.9±0.31 mg GAE/g sample. FRAP value was found to be 48.91±0.33 µmol Fe/g sample and DPPH• scavenging activity was found to be 0.76±0.03 mg/mL. This study is the first report in which the essential oil content of Marrubium parviflorum subsp. oligodon was determined by SPME.