The purpose of our study is to evaluate antibacterial acitivity of the methanolic extracts of 14 medicinal plants 8 of which are endemic species to Anatolia using the Disc diffusion assay. By disk diffusion assay, the antibacterial activity of plant extracts was evaluated by using the noncytotoxic concentrations for Vero cell line determined by MTT assay. The methanolic extracts were evaluated for antibacterial activity against 9 standart strains (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Bacillus subtilis ATCC 6633, Klebsiella pneumoniae ATCC 4352, Staphylococcus aureus ATCC 25923, Staphylococcus marcescens ATCC 13880, Escherichia faecalis ATTC 29212, Staphylococcus enteretidis ATCC 13076 and Proteus mirabilis ATCC 14153) and 11 environmental strains (S.aureus F1, F2, F3, Serratia marcescens F4, F5, F6, F7, P. aeruginosa F8, F9, P. spp. and Salmonella spp.). It was found that three plant extracts from the 14 plants studied had antibacterial activity. Olea europaea L. plant inhibited the growth of Staphylococcus aureus F1 environmental strain, Cotinus coggygria plant inhibited the growth of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Enterococcus faecalis, Salmonella enteretidis, Proteus mirabilis standard strains and Staphylococcus aureus F1, Staphylococcus aureus F2, Staphylococcus aureus F3 environmental strains and Rosa damascena plant inhibited the growth of Staphylococcus aureus F3 environmental strain.