A fermented milk drink having a stable milky white appearance is prepared by adjusting the solids content and pH of a fermented milk to a solids-not-fat content of 0.5 to 2.5% and a pH of 3.00 to 3.45, heating the resultant adjusted fermented milk to a temperature above 60.degree. C. to dissolve milk protein therein, cooling the heated fermented milk and adjusting the pH to 3.5 to 3.8, and heating the fermented milk having a pH of 3.5 to 3.8 to a temperature above 60.degree. C. to cause re-formation of milk protein particles of relatively uniform small particle size to produce the fermented milk drink.