Oxy-fuel combustion is a potential low-emission technique for energy conversion. This paper presents the results of oxy-fuel experiments under high-pressure conditions. The influence of process parameters, such as reactor pressure and temperature, on the emission of NOx, N2O, and other compounds was tested. A new oxy-fuel experimental setup is presented. The experiments were conducted using a laboratory-scale (fuel input of up to 3 kg/h) pressurized fluidized-bed combustor. The feedstock used was "Ziemowit" coal, and the tests were carried out under oxy-fuel and air-fired conditions. The temperature inside the reactor was in the range of 750-900 degrees C. Generally, NOx emission decreases significantly under higher pressure; however, the details of this trend depend upon the experimental conditions. The effects of pressure and temperature on NOx and N2O emissions are discussed.