This study was designed to examine the phytochemical composition of methanolic (M) and hexane extract (H) for Coriandrum sativum (CS) and Cuminum cyminum (CU) and analyzed by gas chromatography-mass spectrometry (GC-MS). Antibacterial activities were examined against four bacterial species (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa), highest antimicrobial activity was recorded against Staph. aureus and P. aeruginosa with inhibition zone 33 and 31.5 mm, respectively using the hexane extract for C. sativum, at a concentration of 100 μL. The best antimicrobial performance was obtained against B. cereus and E. coli with 26.6- and 28-mm inhibition zone, respectively using methanolic extract of C. cyminum, at a concentration of 100 μL. scanning electron microscopy (SEM) examination confirmed that both Staph. aureus and B. cereus cells densities in biofilms was inhibited and growth weakness of microbe's failure of the assembly system of bacterial cells and colony formation, enlargement of some cells, shrinkage of others, and deformation of the bacterial shape as a result of the effect of the two tested plant extracts. The study also found a change in zeta potential (ZP) value for S. aureus from 20.9 mV. to 0.193 mV. and B. cereus from -19.1 mV. to -0.282 mV., as a result of the effect of the extracts of C. sativum and C. cyminum, respectively. The GC-MS forty-two peaks of the compounds detected was shown in Chromatogram GC-MS analysis of hexane extract of C. sativum showed the presence of seventeen major peaks and the components corresponding to the peaks. The first set up peak was determined to be 1,3,5 Cycloheptatriene in area peak equal to 19.71% and methanolic extract of C. cyminum results showed that thirty-two peaks of component detected, the highest component was Benzaldehyde, 4-(1-methylethyl) in area peak equal to 25.73%.