The title compound, C(13)H(18)Br(2)O(3), was prepared by a bromination reaction of (1E,3Z)-methyl 5-oxocyclo-octa-1,3-diene-carboxyl-ate, which was obtained by an ep-oxy-dation reaction of tert-butyl cyclo-oct-1,3-diene-carboxyl-ate. The crystal structure confirms unequivocally the absolute configuration of both chiral centres to be S. In the crystal, C-H⋯O inter-actions link the mol-ecules into chains running along the c axis.