A group-contribution method was developed to predict critical temperature of organic compounds by using only the chemical-structure information. The values of 40 parameters were derived based on the Kurata-Isida equation for critical temperature. With the proposed method, critical temperatures have been calculated for 532 organic compounds and the average absolute error is 12.5 K with a standard deviation of 16.3 K. The overall average absolute percent error is 2.4%. The comparison with the method of Fedors and the method of Joback are also presented.