The present invention provides a method of producing a collagen peptide-containing composition, the method including performing a masking treatment including reacting, in a liquid having a pH of from 5 to 12 at a temperature of from 70° C. to 100° C. for 0.01 hour to 2 hours, a collagen peptide having an average molecular weight of 1,200 or less with a saccharide in an amount of from 0.0001 to 0.05 parts by mass of with respect to 1 part by mass of the collagen, the saccharide being capable of undergoing Maillard reaction with an amino group in the collagen peptide.