This article deals with the quality assurance and improvement of solid recovered fuels (SRF) used for substitution of fossil fuels (e.g. coal) in the cement industry. In order to be able to increase the degree of energy substitution, on the one hand the quality of the SRF has to be increased and on the other hand all possibilities of fuel feeding ports (main burner (SRF PREMIUM Quality), calciner (SRF MEDIUM Quality), etc.) of the ro-tary kiln must be used (Sarc, 2015). In this study, the sieving of a fine fraction after pre-shredding and after post-shredding in a two-stage SRF production process was investi-gated. The fractions resulting from the sieving were examined for their combustion pa-rameters. Extensive sampling and subsequent chemical-physical analysis of the sieve fractions revealed that sieving off the fine fraction leads to an improvement of the com-bustion characteristics of the SRF PREMIUM Quality, but that two heavy metals investi-gated accumulate slightly. The fine fraction (below 20 mm grain size) is very well suited for use in the calciner.