In 2020, Colombia produced 2.4 million tons of cassava (Manihot Esculenta). The production stage of the crop shows an increase in the generation of residual biomass (branches). The disposal of this residual biomass contaminates soils, and water sources and emits greenhouse gases; therefore, the valorization of these residues is necessary within the cassava agro-industrial chain to strengthen its circular economy and contribute to environmental sustainability. This study investigated how temperature affects the mass and energy yield of cassava branches (CB) biochar. CB of the Melúa 31 variety were used, dehydrated, chemically, proximally, and energetically characterized by measuring their high heating value (HHV) and pyrolyzed at maximum temperatures of 300 and 600 °C, at heating rates of 5 and 10 °C/min. The biochar obtained was subjected to HHV tests. The cellulose content was 35.97%, hemicellulose 6.30%, lignin 21.99%, volatile material 80.13% and fixed carbon 13.63%. The best biochar yields were obtained at low temperatures (42.70–43.78%) and at high temperatures, non-condensable gas production was favored (70.12–71.70%). The HHV increased with pyrolysis. CB is a potential feedstock for biochar production. Biochar can be used to improve soil pH and also as a fuel.