Carbonaceous materials with sulfonated solid acid (C-SO3H) can be generated by one-step mild hydrothermal carbonization which stable and monodisperse material. The aims of this research are to produce strong acid catalyst with high acid content and evaluate the performance on esterification of WCO. The carbon material spheres with micrometer sizes will generate from glucose in the present of hydroxyethylsulfonic acid during hydrothermal carbonization at 180 ◦C for 4 h. The esterification of waste cooking oil (WCO) and methanol over solid acid catalyst is potential application to environmentally benign biodiesel production. The esterification reaction was conducted in variation of time (1-4 h) and temperature (50 oC - 80 oC). For the next step, the transesterification using NaOH as catalyst was conducted at 60 oC for 0.5-2 h. The free fatty acid (FFA) value of WCO can be decreased to 93.4% at 60 oC for 3 h. For the transesterification process was gave high yield for biodiesel about 87% in 1 h. The as-prepare solid acid catalyst will design to be an active, stable and reusable solid acid as an environmentally benign replacement for homogeneous catalyst, make it economically viable to compete with commercial petroleum-based diesel fuel.