To compare the chars formed by one-stage and two-stage gasification in an entrained-flow coal-gasifier, the gasification method of entrained-flow-coal-gasifier, gasification tests were carried out using a practical gasifier with a capacity of 25 t/d coal input, in which both operations were possible. Gasification reaction characteristics of the chars formed at high temperature and pressure were examined by thermogravimetric analysis. As the result, the following characteristics were clarified. 1) The gasification rate of the char formed in the one-stage gasification at high temperature condition is lower than that of the char formed in two-stage gasification, which combined high-temperature and low-temperature operations. 2) The char formed in the two-stage gasification is a mixture of small particles formed at high temperature in the first stage and large particles formed at low temperature in the second stage. The gasification reaction of the char progresses in two steps, as such that both types of particle were synthesized. 3) The gasification rate of small particles within the char formed in two-stage gasification is lower than that of large particles within the same char and showed a similar value to that of the char formed in one-stage gasification.