The invention discloses a method for preparing a cochineal aluminum-free lake pigment by using protein, a product and application of the cochineal aluminum-free lake pigment. The method comprises thefollowing steps: adding axinic acid into a buffer solution with a pH value of 3 to prepare a pigment solution, adding metal ions, and carrying out full stirring to obtain an axinic acid pigment solution; adding protein into the axinic acid solution, carrying out full and uniform mixing, adding polyphenol, carrying out uniform stirring, conducting centrifuging, taking a precipitate, freeze-drying the precipitate, and carrying out grinding to obtain the cochineal aluminum-free lake pigment. The method for preparing the cochineal aluminum-free lake pigment by using the protein is simple and convenient to operate; and the product does not contain aluminum, so the safety of the product is prevented from being doubted. According to the cochineal aluminum-free protein lake provided by the invention, the lake has a relatively good color generation effect in an alkaline dilute iron solution and an alkaline calcium solution, and shows a relatively good dyeing effect on dough, minced fillet and single cream.