The objective of this study is to examine how different concentration of neurotransmitters in plasma between patients with dementia and normal people regarding the inhalation of lavender oil. This study subjects were 9 elderly patients with dementia who live in nursing home and 9 normal women. Before and after inhalation, they were collected blood sample. Norepinephrine (NE), serotonin (5-HT), dopamine (DA), and r-aminobutyric acid (GABA) concentration analysis were performed. Before inhalation, dementia patients were significantly different with the normal group in GABA and DA, NE. Following inhalation in experimental group, dementia patients and normal group were only significantly increased in 5-HT. But it did not significantly change in the other neurotransmitters. After inhalation, dementia patients were significantly different with the normal group in GABA and 5-HT. This result suggests that the increase of 5-HT release by the inhalation of lavender oil related to reduce the behavioral and psychological symptoms of dementia.