The present invention aims to provide modified gum arabic having an increased total dietary fiber content and use thereof. The modified gum arabic of the present invention, which is obtained by heating gum arabic, has a total dietary fiber content (determined by AOAC method) of not less than 90%, and preferably has a weight-average molecular weight of not less than 1,000,000. This modified gum Arabic is usable as a dietary fiber material or an additive for enriching dietary fiber to be used in foods, drinks and medicines. Therefore, the present invention provides foods, drinks or medicines containing the above-described modified gum Arabic as dietary fiber material or an additive for enriching dietary fiber.