To provide an agent for improving texture of meat or fish food with which the meat or fish food is made to have soft and meltable texture.

The agent for improving texture of meat or fish food contains whey minerals the calcium content in the solid content of which is less than 2 mass%, preferably whey minerals satisfying following conditions (a), (b), (c), (d) and (e), as active ingredients: (a) an ash content in the solid of the whey minerals is 25-75 mass%; (b) a calcium content in the solid of the whey minerals is less than 5 mass%; (c) a lactic acid content in the solid of the whey minerals is more than 1.0 mass%; (d) aqueous solution having 0.1 mass% of the solid of the whey minerals has pH 6.0-7.5; and (e) a lactose content in the solid of the whey minerals is less than 50 mass%.