Purple nutsedge, Cyperus rotundus L. (Cyperaceae) is an invasive plant grown in all around the world. C. rotundus rhizomes are called "topalak" and an analgesic plant for the treatment of stomach ache in infants, folk medicine in Turkey. The volatile compounds of C. rotundus rhizomes were investigated by Headspace-SPME. Cyperene (30.5% and 28.0%), alpha-copaene (10.6% and 2%) and a-ylangene (7.7% and 10.5%) were identified as main volatile components of rhizomes and analyzed at room temperature and 40 degrees C respectively. This study designed to support detailed studies on underground plant parts volatiles and it is the first time to identification of volatile compounds of raw C. rotundus rhizomes collected from Turkey by Headspace-SPME and GC and GC-MS.