The presence of weeds in the corn plant area is negatively affecting the growth and production of crops if the weeds are not controlled appropriately. This study aims to determine the effect of mycorrhizal fungi on the density of weeds, growth and yield of maize on marginal dry land. The experimental design used in this study was Randomized Block Design (RDB). The tested treatments were the mycorrhizal fungal consisting of 3 treatments: without mycorrhizal fungi propagules (A0), 15 g propagules of mycorrhizal fungi (A1), 30 g propagules of mycorrhizal fungi (A2), each treatment was repeated four times to 12 treatment unit. Observation variables in this research are: density of weed species, plant height, plant stem diameter, length of cob, diameter of cob, number of seeds/cob and percentage of mycorrhizal fungi infections at plant roots. The results showed that the dominant tinds of weeds from broad-leaved i.e.: M. invisa, I. triloba, M. charantia, R. communis, S. torvum, P. niruri, A. conyzoides, A. gracilis, P. longisetumr serta C. plumieri. The dominant kinds of weeds from grasses are: S. viridus, E. indica, D. adscendes, P. repens and C. dactylon. The kinds of weed dominant from sedges is C. rotundus. The length of cob, the diameter of cob and the highest number of seeds were found in treatment A1 with the values of 9.46 cm, 2.45 cm and 190.44 seeds/cobs respectively. The percentage of mycorrhizal fungi infections at the highest root of maize plants occurred at treatment of A2 as 53.33%.
