The essential oil was obtained from the aerial part of Rhododendon mucronulatum Turcz. var. ciliatum Nakai by steam distillation, samples were collected by headspace (HS) and solid-phase microextraction (SPME) methods, and the compositions of the oil were analyzed by gas chromatography-mass spectrometry (GC-MS). Nineteen constituents were identified from the essential oil: 15 carbohydrates, 3 alcohols, and 1 acetates. Major constituents were 2-${\beta}$-pinene (16.1%), camphene (11.9%), ${\delta}$-3-carene (11.4%), d,l-limonene (9.5%), and ${\gamma}$-terpinene (9.5%). By SPME extraction, seventeen constituents were identified: 13 hydrocarbons, 1 alcohol, 1 nitrogen-containing compound, 1 acetate, and 1 amine. Major constituents of the SPME-extracted sample were cam phene (19.6%), 2-${\beta}$-pinene (18.0%), ${\delta}$-3-carene (17.4%), trimethyl hydrazine (9.7%), ${\gamma}$-terpinene (8.5%), and d,l-limonene (5.5%). By HS extraction, thirteen constituents were identified: 11 hydrocarbons, 1 alcohol, and 1 nitrogen-containing compound. Major constituents of the HS-extracted sample were camphene (25.8%), ${\delta}$-3-carene (24.8%), 2-${\beta}$-pinene (20.2%), d,l-limonene (5.4%), tricyclene (5.1%) and trimethyl hydrazine (4.6%). The fragrance of the essential oil was coniferous, balsamic, and woody, and the $IC_{50}$ value of the essential oil was 0.030 ${\mu}g/mg$ in MTT assay using UaCaT keratinocyte cell line.