Cymbopogen citratus and Thymus schimperi are the most common weed plants in Ethiopia and used in traditional medicines. This study was conducted to evaluate the antioxidant capacities by using 2,2- diphenyl-1-picrylhydrazyl (DPPH) scavenging activities and Ferric reducing antioxidant potential (FRAP) as well as to determine the total phenolic content and antimicrobial activities of the essential oils of Cymbopogen citratus and Thymus schimperi. The percentage yields of essential oils of Cymbopogen citratus and Thymus schimperi leaves were 0.58% and 0.47% respectively. The result of total phenolic content of essential oils from Cymbopogen citratus and Thymus schimperi leaves were determined by using Gallic acid as standard were (40.6075 and 27.811) mgGAE/g of EOs respectively. The essential oils of Cymbopogen citratus and Thymus schimperi leaves Percentage DPPH scavenging activity were (28.23%-42.9%) and (26.32%-38.86%) respectively and Percentage Ferric reducing power were (81.8% - 90.07%) and (73.92% -82.32%) respectively. The antibacterial activities of the extracts were investigated against gram positive and gram negative bacteria using Muller Hinton Agar medium by disc diffusion method. After incubation, zone of inhibition was measured in mm. Strong antimicrobial activities were observed in essential oils of Cymbopogen citratus in most microbial strains. In this antimicrobial determination of S.aureus ,S.pyogen, E.coli and K. pneumonia with minimum zones of inhibition (in mm) of Cymbopogen citratus and Thymus schimperi were (12.1±1.63, 10.32±0.81, 13.67±0.24, 12.54±0.81) and (11.5±1.7, 12.07±0.94, 6.5±0.63, 11.6±0.46) were respectively. Generally Cymbopogen citratus extract had good antioxidant and antibacterial activity