Essential oils have recently received a lot of attention due to their numerous uses in natural functional ingredients, Cosmetics, pharmaceutical formulations, and biomedical products. In our research,, the chemical composition and biological effects of four commercial essential oils obtained extracted from four different plants, Zingiber officinale (Ginger), Citrus sinensis (Orange), Cin-namomum camphora (Camphor), and Cinnamomum cassia (Cinnamon cassia) were analyzed and determined. GC-MS was used to analyze the chemical composition of four essential oils. The disc diffusion technique, minimal inhibition concentration (MIC) and minimum bactericidal concentration (MBC) analysis were used to determine the antibacterial effect of essential oils against Gram pos-itive (Bacillus cereus and Staphylococcus aureus) and Gram negative (Klebsiella pneumonia and Escherichia coli ) bacteria. The cytotoxic activity was also evident against cervical carcinoma cells and prostate Carcinoma cells. By GC-MS analysis, the four essential oils, Z. officinale, C. inensis, C. camphor, and C.cassia contained 32, 8, 16, and 9 components in total, respectively. Results, Most IP: 203.8.109.20 On: Fri, 11 Aug 2023 16:29:49 of studied essential oils showed antibacterial activities; C. cassia recorded the highest effect against Copyright: American Scientific Publishers tested strains, followed by C. inensis and C. camphor. C. cassia EO showed a strong inhibitory Delivered by Ingenta action against B. cereus and E. coli by inhibiting the region 45.7 & PLUSMN; 0.55, and 40.5 & PLUSMN; 0.53 respec-tively, while Z. officinale showed no effect against B. cereus, and S. aureus Gve+. The lowest value of MIC and MBC for C. cassia EO is & SIM;25 & mu;L/mL against B.cereus. C. cassia was the most effective against used mammalian Cell Lines (IC50 values of 52.5 & PLUSMN; 1.59 and 47.46 & PLUSMN; 1.28 & mu;g/mL) followed by C. camphora (IC50 values of 53.23 & PLUSMN; 1.68 and 60.64 & PLUSMN; 1.76 & mu;g/mL). Finally, essential oils have shown a good alternative to replace antibiotics and anti cancer drugs.