Four popular spices black pepper (Piper nigrum L.), cumin (Cuminum cyminum L.), coriander (Coriandrum sativum L.) and cardamom (Elettaria cardamomum) were analyzed for their oil composition by GC-MS. Thirty compounds were identified in the black pepper oil and the main components were β-caryophyllene (20.225 %), sabinene (18.054 %), limonene (16.924 %), α-pinene (9.171 %) and α-phellandrene (5.968 %). Twenty five compounds were identified in the cumin oil – cuminaldehyde (30.834 %), 3-caren-10-al (17.223 %), β-pinene (14.837 %), γ–terpinene (11.928 %), 2-caren-10-al (8.228 %) and pcymene (6.429 %). Twenty nine compounds were identified in the coriander oil – β-linalool (58.141 %), α-pinene (8.731 %), γ-terpinene (6.347 %) and p-cymene (5.227 %). Twenty nine compounds were identified in the cardamom oil – α-terpinyl acetate (39.032 %), eucalyptol (31.534 %), β-linalool (4.829 %), sabinene (4.308 %) and α-terpineol (4.127 %). The antimicrobial activity of essential oils against pathogenic (Escherichia coli ATCC 25922, Escherichia coli ATCC 8739, Salmonella sp. (clinical isolate), Staphylococcus aureus ATCC 6538P, Proteus vulgaris G) microorganisms by disc-diffusion method was examined. Gram-positive bacteria were more sensitive to the oils (inhibition zones being between 8 and 12.5 mm) and the minimum inhibitory concentration was more than 600 ppm; Gram-negative bacteria were less sensitive. The obtained essential oils are suitable for use as biopreservative agents.