The increasing demand on new antimicrobial compounds is very important nowadays because the microbes become more resistant to the old antimicrobial compounds. Hence, this study was designed to isolate and identify antimicrobial compounds from Celery seeds (Apium graveolens). The seeds were extracted by hexane, methylene chloride and methanol (sequentially). Purification was achieved by column chromatography. 1-phenyl-1-hepten-3-ol was isolated from hexane extract and the chemical structure was identified by spectroscopic studies (IR, proton NMR and GC-MS). The hexane extract showed the highest value as antimicrobial activity against Bacillus cereus, Salmonella sp., Staphylococcus sp. and Penicillium sp, Fusarium oxysporum, Alterneria solani, and Aspergllus niger. However, the extracts (hexane, methylene chloride and methanol) didn’t show any inhibition zone against Pseudomonas sp.