In the present study, an oxygen blown pilot scale pressurized entrained-flow biomass gasification plant (PEBG, 1 MWth) was designed, constructed, and operated. This Article provides a detailed description of the pilot plant and results from gasification experiments with stem wood biomass made from pine and spruce. The focus was to evaluate the performance of the gasifier with respect to syngas quality and mass and energy balance. The gasifier was operated at an elevated pressure of 2 bar(a) and at an oxygen equivalence ratio (lambda) between 0.43 and 0.50. The resulting process temperatures in the hot part of the gasifier were in the range of 1100-1300 degrees C during the experiments. As expected, a higher A results in a higher process temperature. The syngas concentrations (dry and N-2 free) during the experiments were 25-28 mol % for H-nu, 47-49 mol % for CO upsilon, 20-2,4 mol % for COD and 1-2 mol % for CH4. The dry syngas N-2 content was varied between 18 and 25 mol % depending on the operating conditions of the gasifier. The syngas H-2/CO ratio was 0.54-0.57. The gasifier cold gas efficiency (CGE) was approximately 70% for the experimental campaigns performed in this study. The synthesis gas produced by the PEBG has potential for further upgrading to renewable products, for example, chemicals or biofuels, because the performance of the gasifier is close to that of other relevant gasifiers.