The energy crisis and the demand for increasing the New and Renewable Energy (NRE) mix encourage the utilization of biomass waste as raw material for Refuse Derived Fuel (RDF). Tanah Bumbu Regency has the potential for veneer waste, empty oil palm bunches (EFB), and oil palm fronds which can be converted into valuable alternative energy. This study aimed at analysing the morphological characteristics and elemental composition of the three biomass and determining the most optimal RDF formulation. The study was conducted from August to November 2025 with sampling at PT Hutan Rindang Banua and PT Kodeco Agrojaya Mandiri, and testing at the Integrated Laboratory of University of Lambung Mangkurat and UPTD ESDM Banjarbaru. The methods included purposive–composite and duplex sampling techniques, proximate and ultimate tests, calorific value using a bomb calorimeter, RDF briquette production with composition variations A, B, and C, and morphological and structural analysis using SEM and XRD. The results showed the dominance of lignocellulosic structure with carbon content of more than 80% and good porosity, and the highest calorific value was obtained in composition A (Veneer 45%, 25% OPEFB, 20% Palm Oil Palm Leaf, 10% Plastic) of 7,170.36 kcal/kg, exceeding composition C (7,012.12 kcal/kg) and B (6,949.51 kcal/kg), and far above the minimum standard for RDF co-firing in the cement industry (4,300 kcal/kg). Thus, formulation A is the most optimal RDF composition and local biomass waste has strong potential as a renewable energy source which supports waste management and sustainable energy transition in the industrial sector.