A method for producing a composition containing fucoxanthin includes a first step of adding a water-soluble solvent containing 0 to 80% by weight of water to seaweed to obtain a seaweed component extract, and then adding water and/or a water-soluble solvent to the seaweed component extract in such a manner that the concentration of the water-soluble solvent is 20 to 45% by weight and also adding a diluent thereto to obtain a diluent-containing extract, and a second step of stirring the diluent-containing extract, and then collecting a substance aggregating into the diluent-containing extract as a composition containing fucoxanthin by separation.