Abstract The essential oil obtained by hydrodistillation from the aerial parts of Wedelia glauca (Asteraceae) growing in San Luis, Argentina, was analyzed by GC and GC/MS. Forty-two compounds were identified. The oil was found to be rich in monoterpene hydrocarbons (near 94.9%), such as limonene (38.0%), sabinene (23.9%) and Î±-pinene (22.0%), which were the main components. Key Word Index: Wedelia glauca Asteraceaeessential oil compositionlimonenesabineneÎ±-pinene