Department of Chemistry, Faculty of Science and Technology, Universitas Airlangga, Komplek Kampus C UNAIR, Jl. Mulyorejo, Surabaya, Indonesia Department of Chemistry, Taunggyi University, Shan State (South), Myanmar Faculty of Pharmacy, Meijo University, Tempaku, Nagoya, Japan Department of Chemistry, Mandalay University, Mandalay, Myanmar E-mail: nanik-s-a@fst.unair.ac.id Manuscript received online 21 November 2019, revised and accepted 02 December 2019 Three quaiane-type sesquiterpenes named curcumenol (1), zedoarondiol (2), and (1S,4S,5S,10R)-isozedoarondiol (3) were isolated from the rhizomes of Curcuma comosa. Their structures were elucidated on the basis of extensive spectroscopic analysis. The cytotoxic activities of all isolated compounds were tested by MTT assay. Compounds 2 and 3 showed the most potent activities against T47D cell line with IC50 values 12.13 and 10.93 µg/mL, respectively