The essential oils of the air- dried aerial parts of Parkinsonia aculeate were studied by GC and GC/MS. In parallel the antimicrobial and antioxidant activities were evaluated. The result of GC/MS analysis revealed the presence of forty eight compounds of essential oils. The main components were identified asphenol, 2,4-bis(1-methyl-1-phenylethyl) (41, 13.46%), 2,4-bis(dimethylbenzyl) -6-t-butylphenol (42, 8.19%), dibutyl phthalate (27, 5.52%), nonadecane (38, 4.57%), phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methyl-1-phenylethyl) (29, 4.39%), ethyl iso-allocholate (31, 4.10%) and heptadecane (35, 4.03%). In addition, minor components were also detected in the essential oil as butylatedhydroxytoluene (14, 1.53%), Phenol,2-(1,1-dimethylethyl)-4-(1,1,3,3-tetramethylbutyl) (21, 1.0%), 1,2-Benzenedicarboxy-lic acid, bis(2-methylpropyl) ester (23, 0.9%), 1-Hexadecanol (24, 1.03%), Phenol,-(1,1-dimethylethyl)-4-(1-methyl-1-phenylethyl) (28, 2.89%), phytol (30, 2.55%) and eicosanoicacis (32, 1.65%). Essential oil showed moderate antimicrobial activity against bacteria and fungi. Furthermore, the essential oil of this plant deprived from antioxidant activity.