The paper discusses the influence of the pressure of pyrolysis on the formation kinetics of C-1-C-3 hydrocarbons, hydrogen, CO and CO2 during pyrolysis of three selected coals of different rank. The examinations were carried out within the pressure range of 0.1-10 MPa under the conditions of constant residence time of primary products in the reaction zone. It was found that the pressure of pyrolysis exerts a significant influence on the formation rate of CH4, H-2, CO and CO2. Also, the formal kinetic parameters of formation reactions of major gaseous products during pressure pyrolysis of the examined coals were calculated. (C) 2003 Elsevier Ltd. All rights reserved.