A chlorella extract-containing product of excellent safety and storage stability is provided without using a benzoate, which is a common preservative. A chlorella extract-containing product containing a capsicum extract at 0.020-1.63% by weight on a dry weight basis relative to a chlorella extract in an aqueous liquid for drinking having the chlorella extract as an principal ingredient. This chlorella extract-containing product is to be used as a chlorella-containing beverage or a chlorella-containing food additive. A method for improving the storage stability of a chlorella extract-containing product, comprising adding a capsicum extract to a chlorella extract at 0.020-1.63% by weight on a dry weight basis in an aqueous liquid for drinking having the chlorella extract as an principal ingredient.