Inulinase is an enzyme that converts inulin to fructose. This enzyme can be isolated from the endophytic mold of red dahlia tubers (Dahlia sp.L). The most critical steps to producing large-scale inulinase enzymes are to separate endophytic molds, then identify the type of mold and assess the best activity of the inulinase enzyme based on temperature and PH. The method is to isolate endophytic molds, make crude enzymes with Potato Dextrose Broth (PDB) media and fermentation culture, test the optimum PH of the inulinase enzyme, and conduct molecular identification of endophytic molds with ITS1 and ITS4 primers. The results obtained were the isolation of the red dahlia tuber mold, and five isolates were obtained, namely UD 1, UD 2, UD 3, UD 4, and UD 5. The results of qualitative inulinase screening by measuring the clear zone were UD 1:>2 (+ ++), UD 2:>2 (+++), UD 3: <1-2 (++), UD 4: < 1 (+), and UD 5: <1-2 (++). The result of the highest inulinase measurement at UD2 based on variations in temperature and PH was at a temperature variation of 350C and PH 6.0 was 1.322222222, and the lowest was at a temperature variation of 50 and PH 4.0 was 0.282716049. The result of identifying molecular based on BLAST analysis found Fusarium sp species, thus adding a new variant of the inulinase enzyme from red dahlia tubers that can be used by industry to produce fructose through enzymatic reactions.