In order to test the importance of using some medicinal plants in indigenous medicine system to treat various diseases, this study examined the antimicrobial effects of aqueous extracts resulted by decoction and infusion of a local plants from Algerian South-west zone: Atriplex halimus L. andFicus caricaL. The antimicrobial properties were examined by disc-diffusion technique against eight (08) bacterial strains, and one (01) strain of fungus. The minimum inhibitory concentration (MIC) and interaction tests, between the different bacteria, fungi and plants extracts were determined by the checkerboard method on Petri dishes. Phytochemical composition analysis allowed for the quantification of total polyphenols, flavonoids and anthocyanins contents of plants aqueous extracts. The decoction of Atriplex halimus inhibits the growth of both Staphylococcus aureus and Pseudomonas aeruginosa species inside inhibition areas with diameters about 13.5 and 14 mm, respectively.The infusion presents an appreciable inhibitory action with an inhibitionzone of 16 mm against Salmonella typhimurium. Both two extracts of Ficus caricawere inactive against all the microbial species tested.