The use of a granulated xanthan gum comprising, relative to 100% by mass of the granulated xanthan gum: xanthan gum granules having a degree of hardness of 2 N or higher and lower than 8 N in an amount of 5% by mass or higher; and xanthan gum granules having a degree of hardness of 8 N or higher in an amount of 20% by mass or lower makes it possible to provide a granulated xanthan gum and a thickening composition comprising the granulated xanthan gum which undergo suppressed formation of unmixed lumps in a wide variety of water-containing foods such as water, teas, refreshing beverages, dairy beverages, soups, and thick liquid foods, even when the xanthan gum concentration is 50% by mass or higher.