Chemical and electrophysiological analyses and field trials were used to identify the female sex pheromone of Copitarsia decolora (Guenée) (Lepidoptera: Noctuidae). Coupled gas chromatographic-electroantennographic detection (GC-EAD) analysis of the female gland extract showed the presence of two EAD-active peaks, which were identified by GC-mass spectrometric (MS) analysis as (Z)-9-tetradecenyl acetate (Z9–14:Ac) and (Z)-9-tetradecenol (Z9–14:OH). The field evaluation of the EAD-active compounds indicated that traps baited with either Z9–14:Ac or Z9–14:OH caught few males. In contrast, traps baited with the binary blend of both components caught significantly more males than traps baited with the single compounds. Captures in traps baited with a mixture of Z9–14:Ac and Z9–14:OH at 4:1, 10:1, and 100:1 ratios were not significantly different from the catches in traps baited with virgin females. Few males were captured in traps baited with a blend of Z9–14:Ac and Z9–14:OH at 1:4, 1:10, and 1:100 ratios.