Abstract: The chemical composition of the essential oil obtained from the fruits of Pimpinella affinis Ledeb. (Apiaceae) was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. Twenty-four components were identified in the essential oil of P. affinis Ledeb., whose major constituents were geijerene (17.68 %), limonene (12.86 %), pregeijerene (9.92 %), germacrene D (8.54 %) and trans- -cimene (4.94 %). The essential oil was evaluated for antibacterial and antifungal activities. The oil showed antimicrobial activity against all the tested microorganisms, excepted Pseudomonas aeruginosa. Maximum activity was observed against fungal microorganisms.