The paper presents results of laboratory studies on the possibility of co-incineration of sewage sludge with waste rubber, as the possibility of thermal treatment of both: sludge and examined waste. Municipal sewage sludge, taken from the Wastewater Treatment Plant in Tychowo and waste bicycle tires ware used in the examinations. In addition, results were compared with the results of coincineration of analysed sewage sludge mixed with hard coal as classic fuel. The initial stage of the study was a technical analysis of materials used in the examinations. Results of the analysis of exhaust gas fluxes, resulting from the co-incineration of examined waste and sewage sludge were presented and evaluated in the next part of paper. Following parameters were determined: cSO₂ – concentration of sulfur oxide (IV), cNOx –concentration of nitrogen oxides. Variable independent parameters determined during studies of mixtures incineration were: mass fraction of sludge in the fuel mixture, temperature in the combustion zone of the furnace and the excess air coefficient. Analysis of energetic properties and emissions of pollutants, under tested conditions of incineration of those mixtures, allowed determining the maximum share of sewage sludge in the fuel mixture and impact of variability of independent parameters of the incineration process on the quality of this process. Final analysis of energetic properties of mixtures and results of examinations on incineration conditions of those mixtures proved, that maximum mass fraction of sewage sludge should not exceed 10%. Increase of incineration temperature significantly decreases quality of thermal processing of examined sewage sludge, increasing emissions of sulfur oxide (IV) and, to a greater extent, of nitrogen oxides NOx. Increase of oxygen amount, along with air fed into incineration chamber caused, causes increase of nitrogen oxides emission and slight changes of sulfur dioxide concentration.