This paper describes an experiment of underground coal gasification in experimental equipment. The experiment was done within the range of the project APVV-0582-06, in May 2010. During the period of 63 h there was gasified amount of 214 kg of coal in experimental gasifier with average rate of 3.4 kg/h. The air, was the primary gasification agent in the experiment and its total volume was 661 Nm(3). Oxygen was used only in a short period of the experiment. The produced gas reached an average calorific value of 3.27 MJ/Nm(3). The calorific value was slightly higher (4.13 MJ/Nm(3)) when was using oxygen as gasification agent. This article talks not only about the analysis of the achieved results from UCG but also used experimental gasifier, input supply system of a gasification agent, and monitoring system. (C) 2016 Elsevier Ltd. All rights reserved.