This research aimed to develop briquette biomass from herbal waste and mangosteen branch residue from agriculture. The influence of the ratio of herbal waste to mangosteen branch on the properties of the briquette biomass was investigated. Dried herbal waste and mangosteen branches were mixed in predetermined ratios and bonded with tapioca starch. The briquette biomass’s calorific value and moisture content were analyzed according to ASTM D5865 and ASTM D3173 standards, respectively. Boiling water experiments also tested the properties of the briquette biomass.