In this study, the antimicrobial activities of several parts of various trees grown in the Kahramanmaraş region of Turkey were investigated by the disc diffusion method. Chloroform, acetone and methanol extracts of leaves, resins, barks, cones and fruits of Pinus brutia Ten., Juniperus oxycedrus L., Abies cilicia Ant. & Kotschy Carr., Cedrus libani A. Rich. and Pinus nigra Arn. were prepared and tested against Bacillus megaterium DSM 32, Bacillus subtilis IMG 22, Bacillus cereus FMC 19, Escherichia coli DM, Klebsiella pneumoniae FMC 3, Enterobacter aerogenes CCM 2531, Staphylococcus aureus Cowan 1, Mycobacterium smegmatis RUT, Proteus vulgaris FMC 1, Listeria monocytogenes Scoot A, Pseudomonas aeruginosa DSM 5007, Candida albicans CCM 314, Candida tropicalis MDC 86 and Penicillium italicum K. The results showed that antifungal effects were not observed for the whole extracts, E. coli was not inhibited by any of the plant extracts except by the chloroform and acetone extracts of the leaves of A. cilicia, which showed inhibition zones of 16-18 mm, respectively. All the plant extracts used in this study inhibited the development of the other bacteria studied. When the results of this study were compared with an ampicillin standard, it was found that the microorganisms studied were generally susceptible, intermediate or resistant to the extracts of species when compared with the ampicillin standard. On the other hand, the acetone and methanol extracts of Juniperus fruits were found to be quite resistant.