Introduction: Microcrystalline cellulose is one of the cellulose derivatives widely used in the pharmaceutical industry as an excipient in the manufacture of tablets. Unfortunately, most of these filler materials are still largely imported. On the other hand, Indonesia has huge potential to generate microcrystalline cellulose from agricultural waste or weeds such as oil palm empty fruit bunch and water hyacinth. The purpose of this study was to find a potential cellulolytic mold and raw material for preparation of microcrystalline cellulose by enzymatic hydrolysis. Method: The potential cellulolytic mold was obtained from rotted oil palm trunk, and alpha cellulose was prepared by digesting raw material powder by the alkaline condition. Cellulase enzymes are obtained through extraction from the cellulolytic mold and used to treat alpha cellulose at a concentration of 2, 6 and 10 % v/v, respectively. Then, the resulted microcrystalline cellulose was identified by SEM (Scanning Electron Microscope) and XRD (X-Ray Diffraction) and compared with reference Avicel pH 101. Results: The results showed that crude enzyme of isolated mold has better activity than