Teki (Cyperus rotundus L.) mempunyai kandungan senyawa bioaktif pada umbi dan daunnya. Senyawa bioaktif tersebut dapat digunakan sebagai penolak serangga, antifungus, antimikroba, toksin dan menjadi pertahanan bagi tumbuhan terhadap predator. Saponin pada umbi teki termasuk kelompok antibakteri yang dapat mengganggu permeabilitas membran sel mikroba, yang mengakibatkan kerusakan membran sel dan menyebabkan keluarnya berbagai komponen penting dari dalam mikroba. Uji daya antibakteri ekstrak umbi teki terhadap bakteri Staphylococcus epidermidis dan Propionibacterium acne menunjukkan adanya zona hambat di sekitar kertas cakram pada konsentrasi 20%, 40%, 60%, 80%, 100%, dan kontrol positif, sehingga ekstrak umbi teki berpotensi sebagai antibakteri Staphylococcus epidermidis dan Propionibacterium acne. Tujuan penelitian ini untuk mengetahui kandungan fitokimia umbi teki dan uji efikasi antimikroba serta mengetahui konsentrasi hambat minimum dari ekstrak kasar umbi teki terhadap pertumbuhan mikroba Propionibacterium acne. Umbi gulma rumput teki diambil dari sekitar perkebunan warga Talang Sari Kota Samarinda. Kemudian dilanjutkan dengan pembuatan simplisia, pembuatan ekstrak kasar ethanol, skrining fitokimia umbi rumput teki (kandungan alkaloid, flavonoid, fenolik, triterpenoid, saponin) serta uji aktivitas antimikroba (Propionibacterium acne). Hasil uji fitokimia menunjukkan bahwa senyawa bioaktif yang terkandung dalam ekstrak kasar ethanol umbi teki adalah fenolik, flavonoid dan triterpenoid. Hasil uji aktivitas antibakteri diperoleh bahwa ekstrak kasar umbi teki yang diujikan pada bakteri Propionibacterium acne dengan konsentrasi 6%, 8%, 10%, 12%, 15% menghasilkan diameter zona hambat berturut-turut 8,6 mm, 10 mm, 11 mm, 11,6 mm, dan 12,6 mm. Nilai Minimum Inhibitory Concentration (MIC) adalah 6%. Teki (Cyperus rotundus L.) contains bioactive compounds in its tubers and leaves. These bioactive compounds can be used as insect repellents, antifungals, antimicrobials, toxins and as a defense for plants against predators. Saponins in teki tubers are an antibacterial group that can interfere with the permeability of microbial cell membranes, resulting in damage to cell membranes and causing the release of various important components from the microbes. Antibacterial activity test of teki extract against Staphylococcus epidermidis and Propionibacterium acne showed an inhibition zone around the disc paper at concentrations of 20%, 40%, 60%, 80%, 100%, and positive control, so that the nutmeg extract has the potential as an antibacterial for Staphylococcus. epidermidis and Propionibacterium acnes. The purpose of this study was to determine the phytochemical content of teki tuber and antimicrobial efficacy test and to determine the minimum inhibitory concentration of the crude extract of teki tuber on the growth of Propionibacterium acne microbes. The sedge weed bulbs were taken from around the plantations of Talang Sari residents, Samarinda City. Then proceed with the manufacture of simplicia, manufacture of crude ethanol extract, screening of nutgrass tuber phytochemicals (contains of alkaloids, flavonoids, phenolics, triterpenoids, saponins) and testing of antimicrobial activity (Propionibacterium acne). The results of the phytochemical tests showed that the bioactive compounds contained in the crude ethanol extract of teki tubers were phenolics, flavonoids and triterpenoids. The results of the antibacterial activity test showed that the crude extract of teki tubers tested on Propionibacterium acne bacteria with concentrations of 6%, 8%, 10%, 12%, 15% produced inhibition zone diameters of 8.6 mm, 10 mm, 11 mm, respectively. 11.6mm, and 12.6mm. Minimum Inhibitory Concentration (MIC) value was 6%.