Salvia x jamensis J. Compton is a hybrid between Salvia greggii A. Gray and Salvia microphylla Kunt. In this study, we describe three hair types identified by Scanning Electron Microscopy. In the essential oil of the aerial parts of S. jamensis 56 different compounds were identified. The two main constituents were β-caryophyllene (14.8%) and β-pinene (6.8%). Cytotoxic-apoptotic activity of S. x jamensis essential oil has been investigated by using U937 cell line. The essential oil EC50 for cell number and for cell apoptosis have been shown to be 360 and 320 µg mL(-1), respectively. Among the constituents of the oil examined, only β-caryophyllene, β-pinene and α-pinene displayed cytotoxic and apoptotic activities. For the first time, it has been demonstrated that some of the pure constituents identified within S. x jamensis essential oil are responsible for its cytotoxic-apoptotic activity when properly combined.