Provided is a treatment method for a lacto-N-biose-containing solution. Said treatment includes preparing a lacto-N-biose-containing solution with a pH of 2.0-5.5 at 25°C, and subjecting said solution to heat treatment at a temperature 65°C or higher. Specifically provided are: a treatment method in which the lacto-N-biose-containing solution is subjected to the heat treatment at a temperature of 65°C or higher while limiting thermal decomposition of the lacto-N-biose； the lacto-N-biose-containing solution which has undergone the aforementioned treatment and a dried substance thereof； and a manufacturing method for products containing lacto-N-biose.
