•Carbonized Refuse Derived Fuel may be qualified as 1st class quality fuel.•Torrefaction allows on RDF/SRF improvement, and recycling as a CRDF.•Torrefaction temperature has an effect on Carbonized Refuse Derived Fuel properties. The influence of Refuse Derived Fuel (RDF)/Solid Recovery Fuel (SRF) torrefaction temperature on product characteristic was investigated. RDF/SRF thermal treatment experiment was conducted with 1-h residence time, under given temperatures: 200, 220, 240, 260, 280 and 300°C. Sawdust was used as reference material. The following parameters of torrefaction char from sawdust and Carbonized Refuse Derived Fuel (CRDF) from RDF/SRF were measured: moisture, calorific value, ash content, volatile compounds and sulfur content. Sawdust biochar was confirmed as a good quality solid fuel, due to significant fuel property increase. The study also indicated that RDF torrefaction reduced moisture significantly from 22.9% to 1.4% and therefore increased lower heating value (LHV) from 19.6 to 25.3MJ/kg. Results suggest that RDF torrefaction may be a good method for increasing attractiveness of RDF as an energy source, and it could help unify RDF properties on the market.