A method for producing a nutritional composition according to the present invention is a method for producing a nutritional composition containing a protein and a mineral group comprising at least two minerals and comprises adding (a) a powder or an aqueous solution of at least one mineral that can be converted into the form of a bivalent ion when prepared into an aqueous solution or (b) a mineral powder mixture comprising at least one mineral that can be converted into the form of a bivalent ion when prepared into an aqueous solution and at least one another mineral that is included in the mineral group to an aqueous protein rich solution containing a whey protein in such an amount that the mass of a protein derived from the whey protein becomes 2 to 12 g/100 ml and agitating the resultant mixture. In the method when there is any remaining mineral spices among the mineral group a powder of the remaining mineral spices is also added to the above mentioned aqueous protein rich solution simultaneously or sequentially and then agitating the resultant mixture.
