Biodiesel is a renewable fuel synthesized from various plant and animal sources. Transesterification, which includes reacting fats or oils with alcohol in the existence of a catalyst, is the primary process used to produce biodiesel. The quality of the oil or fat, particularly the quantity of free-fatty-acids (FFAs) that may impede the reaction, determines the kind of catalyst that is employed. Homogeneous catalysts, such as alkali or acid, are effective for oils or fats with low FFAs but have several drawbacks. However, heterogeneous catalysts are more attractive alternatives for biodiesel production because they are safer, cheaper, easier to separate and reuse, and more tolerant of FFAs. They can be prepared by modifying the surface of carbon materials with acidic or basic groups. The large porosity and surface area of carbon-based catalysts improve their catalytic activity and selectivity. Additionally, it may be produced from waste biomass, like bagasse from sugarcane, which increases the sustainability and environmental friendliness of biodiesel manufacturing. This chapter details the source of used cooking oil waste, various catalysts made from waste biomass resources for biodiesel synthesis, and difficulties and opportunities for the future.