Aerial parts of aromatic grass, Cymbopogon parkeri STAPF, were collected at flowering stage from Kerman province of Iran. The essential oil of air dried samples obtained by hydro-distillation method. The compositions of the essential oil were determined by the use of GC and GC-MS. Nineteen (98.7%) constituents were identified. The main constituents were piperitone (80.8%), germacrene-D (5.1%), santolinyl acetate (2.1%) and alpha-eudesmol (2.1%).