A method of efficiently heightening the emulsifying power of gum arabic, i.e., a process for producing gum arabic with excellent emulsifying power. Also provided is a method by which gum arabic modified so as to have higher emulsifying power is obtained without causing a problem that it becomes a candy-like mass or adheres to the container and without arousing a trouble that it dries excessively or scorches. The method can be practiced by heating gum arabic (raw material) under dry conditions, preferably under the conditions of a drying loss of 3% or less.