Bisham (Commiphora gileadensis L) is one of most well known plant used in Yemen as traditional medicine. The bark of plant was used in the treatment of burns and skin infection. This study aimed to investigate the antimicrobial activity, toxicity and LD50 of methanolic extract of bark of Commiphora gileadensis L, in addition to the phytochemical screening. The results showed that the methanolic extract of bark of plant showed an activity against Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candia species. In addition the extract was safe in mice up to 5 g/Kg. the phytochemical screening showed the presence of flavonoids, phenol, saponin, steroids and amino acids, steroids and amino acids in plants.