The present invention relates to a fermented milk composition containing a cellulose ether and a production method therefor. The fermented milk composition contains a cellulose ether as a stabilizer for preventing whey separation, and the method for producing the fermented milk comprises the steps of: producing a fermentation base； producing a cellulose ether syrup； and introducing the cellulose ether syrup into the fermentation base and homogenizing and cooling same. Accordingly, the fermented milk composition is provided with phase stability by applying thereto a small amount of the cellulose ether, instead of pectin, as a stabilizer for preventing whey separation and can provide a fermented milk beverage having reduced sourness.
