Volatile compounds in Tapinoma melanocephalum (Fabricius) (Hymenoptera: Formicidae, Dolichoderinae) workers were analyzed using gas chromatography–mass spectrometry and electroantennogram responses of workers to these compounds were investigated using coupled gas chromatography–electroantennographic detection. Among 18 detected compounds, six elicited electroantennogram response, including 6-methyl-5-hepten-2-one, 4 iridodials, and (Z)-9-nonadecene. (Z)-9-Nonadecene and iridodials were identified the first time in T. melanocephalum. (Z)-9-Nonadecene is a major component in mandibular glands and iridodials are produced in pygidial glands. In contrast to previous report, actinidine was not found in pygidial glands. Behavioral response of workers to the synthetic (Z)-9-nonadecene was investigated. (Z)-9-nonadecene is an attractant to T. melanocephalum. It also affected their locomotion patterns.