The use of medicinal and aromatic plants species in Yemen goes back thousands of years, and form an important part of the culture, some of the plants still play important role in the health and body care system. Plants are the major sources for various therapeutic agents in the treatment of a wide variety of diseases. The potency of herbal drugs against diseases is mainly due to their chemical compounds. The herbal products today symbolize safety in contrast to the synthetics. Our study aimed at detection and determination of the chemical and phytochemical composition, estimation of antioxidant and antimicrobial activities of eight Yemeni plants: Aloe perryi, Apium graveoleus L, Commiphora myrrha, Lupinus termis, Morus alba, Nigelle sativa L, Portulaca oleracea L, Trigonella foenum L. Estimation Antioxidant activity was carried out in vitro by DPPH, hydrogen peroxide, reducing power and total antioxidant capacity methods. Evaluation Antimicrobial study was carried out using disk diffusion method. It used, 7 bacteria, 1 fungi, and 1 yeast pathogenic strains.