Eucalyptus is one of the most important and highly exploited genus in family Myrtaceae. An UPLC/PDA/ESI-qTOF-MS method was adopted to identify Eucalyptus sideroxylon Cunn. ex Woolls leaves phytoconstituents. Cytotoxicity of E. sideroxylon leaves phloroglucinol-rich extract (PGRE) on VERO cells was