Provided is a method for producing fermented milk having excellent quality, made by mitigating physical changes resulting from aggregation of lactoprotein, which occurs while the fermented milk is stored under refrigeration or being transported. The method for producing fermented milk is characterized in that at least one of the following processes (A)-(C) is performed in (1) a step for preparing a fermented milk mix, (2) a step for heat-sterilizing the fermented milk mix, and (3) a step for adding starter to the fermented milk mix to cause fermentation: (A) a process for adding glucose oxidase to the fermented milk mix having a glucose concentration of 0.05 wt% or less and preparing the fermented milk mix under this glucose concentration condition during step (1) (B) a process for adding glucose oxidase to the heat-sterilized fermented milk mix having a glucose concentration of 0.05 wt% or less prior to step (3) or (C) a process for adding glucose oxidase to the fermented milk having a glucose concentration of 0.05 wt% or less after step (3), the fermented milk having been prepared in step (3).