Henry's constants of carbon dioxide in methanol in the temperature range of 250-500 K are experimentally obtained. The Henry's constants at low temperatures are measured by a gas stripping method, and a similar method is applied to measure the Henry's constants at high temperatures up to the critical point of methanol. The rigorous formula for evaluating the Henry's constants from these measurements is applied to the data reduction for these highly volatile mixtures. By using this formula, a volume effect of vapor phase is discussed. The plot of Henry's constants versus temperature goes through a maximum and approaches an unique point at the critical temperature of methanol. (C) 2004 Elsevier B.V. All rights reserved.