The vision of producing sustainable and renewable bioenergy is to contribute reducing the current global warming impact. It is well known that microorganisms can produce fuels, such as ethanol, butanol, methane, and hydrogen. Alternatively, microbes can produce electricity by means of microbial fuel cell (MFC). The recent development in energy biology has demonstrated the potential of MFC for commercial applications in converting renewable biomass and organic waste into electricity. The biomass sources are highly desirable because they are “carbon-neutral.” Electrical energy can be extracted from organic waste matter and renewable biomass by microbial degradation. The major challenge of using microbial fuel cell is to increase power density for most of the envisaged applications, such as power monitoring electronic devices, light source of battery charger in off-grid areas. A wide scope lies ahead in the scaling up of MFC for large-scale conversion of organic waste and biomass into electricity for powering vehicles, mobile electronic devices or buildings. The use of waste organic from biomass is environment-friendly and regarded as a renewable energy source. This article gives an overview of microbial fuel cell that covers the bioelectrochemical mechanisms, system and components, characterization, performance, and applications.