Thevetia peruviana and Plumeria rubra (family Apocyanaceae) are shrubs cultivated in Egypt for ornamental purposes. This study was done to compare the volatile oils of T. peruviana and P. rubra which were prepared by using the hydrodistillation method from fresh flowers and leaves of each plant. Identification and quantification of the oil components were carried out by GC/MS analysis. The major components of T. peruviana flowers oil were Nonadecane (37.69 %), followed by 1-Nonylcycloheptane (18.39%), while Perilla alcohol (20.49%), β-ylangene(10.62%) and β-Elemene (7.19%) were predominant in the leaves oil. On the other hand, the major constituents of P. rubra flowers oil were Methyl dihydroepi-jasmonate (35.41%), Linalool (14.31%) and Methyl jasmonate (11.99%), while 1-Nonylcycloheptane (32.16%) and Menthol (17.89%) were of highest abundance in the leaves oil. Also, the antimicrobial activity was investigated against Staphylococcus aureus ATCC 4175, Escherichia coli ATCC 10536, Pseudomonas aeruginosa CNCM A21, and Candida albicans ATCC 60193. The minimum inhibitory concentrations (MIC) were determined and compared with those of standard antibiotics (Ofloxacin and Amphotericin B), the tested oils showed a good inhibitory effect against the investigated microbial strains with a minimum inhibitory concentration (MIC) range of 25 to 300 µg/mL except for the P. rubra leaves oil, which showed no activity against Pseudomonas aeruginosa.