Fermentation is one of the necessary processes in the production of bioethanol. Reducing sugar from cellulose will convert it into bioethanol with microorganisms as catalysts. Microorganisms used in bioethanol production also need to be considered and adjusted to the selection of the fermentation process. A previous study examined bioethanol production. However, many still get relatively low yields and require a long time of fermentation to produce bioethanol. Also continuously developing to obtain bioethanol with high yield. The fermentation process included Separate Hydrolysis Fermentation (SHF), Simultaneous Saccharification and Fermentation (SSF), and Consolidated BioProcessing (CBP). The fermentation process has its respective advantages and disadvantages, mainly when applied to lignocellulosic-containing materials. This review will explain and develop future trends in each method.