This study is to assess the antimicrobial and antiradical activities of organic extracts from the species Pulicaria arabica (L.) Cass. We used four clinical strains and four reference strains, to assess the antimicrobial activity of organic extracts of P. Arabica (L.) Cass. Evaluation of the antiradical activity is done by spectroscopic assay using the DPPH (1,1-diphenyl-2-picrylhydrazyl) method. Measurement of the antiradical activity of three plant extracts was carried out using the DPPH test. The anti-radical tests of ours extracts were assessed using the free radicals DPPH catching method. The results showed clearly, that the methanol extract (EMeOH) had the best anti-radical ability followed by chloroform extract (EDCM) and lastly the hexane extract (In-Hex). The antimicrobial tests were evaluated against reference pathogenic strains and others isolated from pathological materials, using agar diffusion method. The results indicated that the apolar extracts (hexane and chloroform) had inhibitory activity against a number of microorganisms higher than that of the polar methanolic extract. Antimicrobial and antiradical activities of organic extracts from the species Pulicaria arabica (L.) Cass has shown that these extracts have considerable inhibitory activity against certain germs and good potential of DPPH free radical scavenging, but these activities are generally lower than those obtained with the reference products (antibiotics, antifungal and ascorbic acid).