The paper presents the results of measurements of the concentration of hydrogen chloride (HCl) and fluoride compounds (as HF) in raw and purified combustion gases discharged from the incineration of selected hazardous wastes. The study included two installations operating on an industrial scale: a multiple hearth furnace and a rotary kiln incinerator equipped with a single wet flue gas cleaning systems. In the multiple hearth furnace was being incinerated sludge from coke industry. In the rotary kiln were being incinerated coal (coke) tars, contaminated cleaning rags, sawdust, used gloves, outdated pharmaceuticals and medicines, hospital waste, waste paints, varnish and lubricant, resin and rubber waste. The emissions of HCl and fluorine compounds from these waste incineration did not exceed the emission limit values established in EU. The highest concentrations of these pollutants were measured during incineration of sewage sludge in the multiple hearth furnace. Nevertheless, in terms of the quantity of incineration wastes, the highest measured emissions (emission factors) were those from the rotary kiln. English title: Emission of hydrogen chloride and fluoride compounds from hazardous waste incineration.