Introduction: Hymenocrater is an important genus of Lamiaceae family. Hymenocrater platystegius is one of species in this genus and this plant is endemic to Iran and it grows wildly in the north east of Iran. The aim of this study was to investigate the chemical composition of Hymenocrater platystegius and to study the neuroprotective effect of essential oil of this plant in H2O2 –induced neurotoxicity in PC12 cells. Materials and Methods: The essential oil was extracted by hydrodistilation of air-dried sample for 5 hours. The essential oil composition of the aerial parts of Hymenocrater platystegius was studied by gas chromatography mass spectrometry. Finally, we treated PC12 cells with the essential oil of Hymenocrater platystegius. Results: The yield of essential oil was 0.1 % (w/w). Fifty-nine compounds were identified representing about 84.72% of the total oil. The major components of this oil were 1, 8-cineole (14.27%), ß-pinene (4.89%), Terpinolene (4.83%), and Sabinene (4.59%). In addition, the data showed that the essential oil decreased oxidative stress-induced PC12 cells death. Conclusion: The results suggest that Hymenocrater platystegius could be a potential candidate for treatment of neurodegenerative diseases.