Results of measurements of solubility of tetracosane in ethane and ethylene are presented. Measurements for the system tetracosane+ethane were performed at 310.15, 330.15 and 350.15 K, and those-for the system tetracosane+ethylene at 330.15 and 350.15 K. Investigations were performed in a wide pressure interval in the vapour-liquid equilibrium region. For the measurements a flow method was applied. For both systems the dew point lines at experimental temperatures were calculated with the Peng-Robinson equation of state. The results of the measurements and the calculations are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.