A research aims to determine the effect of Gunungkidul indigenous mycorrhizal inoculum on cassava Renek varieties. Experimental research on Mediterranean land, which was compiled in a Complete Randomized Block Design (RCBD) using a single factor treatment design with the addition of an indigenous Gunungkidul mycorrhizal inoculum, consisting of 4 forms, namely: A. Pure mycorrhiza; B. Crude inoculum; C. Pellet inoculum; D. Observation parameters include the percentage of mycorrhizal infections in cassava plant roots, number of spores, root length, root fresh weight, root dry weight, root poliferation, plant height, crown fresh weight, crown dry weight, number of leaves, leaf area, number of tubers per plants, cassava length, cassava diameter, cassava weight, and cassava yield. The results showed that the administration of indigenous Gunungkidul mycorrhizal inoculums had no significant effect on the development of mycorrhizae and plant growth as well as the yield of Renek varieras cassava in Mediterranean soil. In the percentage parameter of mycorrhizal infection, the number of spores and leaf area giving the form of mycorrhizal inoculum gives a significantly different effect compared to without mycorrhizal administration. The best form of mycorrhizae inoculum is crude inoculum. This is patented in making the form of mycorrhizal crude inoculum easier.