Disclosed is a method for preparing purple sweet potato Sikhye. The method for preparing purple sweet potato Sikhye is characterized by comprising the steps of mixing malt and cold water at a weight ratio of 1:5 or more to macerate the malt for 20 minutes or more, kneading the malt in the macerated state, then pressing the malt through a filter net, and washing the malt 4 times or more by using the water used during marceration, to thereby obtain a malt leachate mixing glutinous rice and nonglutinous rice at a ratio of 2:1 and washing the mixed rice, then macerating the mixed rice in water for 4 hours or more, and preparing and cooling hard-boiled rice mixing the hard-boiled rice and the malt leachate and preparing Sikhye by maturing and saccharifying the resultant mixture at a temperature of 50°C to 60°C for 5 hours or more until grains of the hard-boiled rice are floated washing and decorticating purple sweet potato to fully mature the purple sweet potato picking up the fully matured purple sweet potato and pulverizing the fully matured purple sweet potato in a pulverizer mixing the pulverized purple sweet potato and the Sikhye to boil the resultant mixture and removing bubbles generated the boiling step, and turning down a lever of a gas range to a middle level 3 minutes after the resultant mixture is boiled to a temperature of 100°C and then further heating the resultant mixture for 40 minutes to 60 minutes. According to the present invention, the availability for nutritional contents that are abundant in the purple sweet potato, is improved, the consumption of sugar is reduced, and additives such as an artificial flavoring and a synthetic food dye are not used. Therefore, a purple sweet potato Sikhye with the unique flavor of the purple sweet potato may be prepared, thereby satisfying consumers that have high preferences in natural foods.자색고구마 식혜 제조 방법이 개시된다. 본 자색고구마 식혜 제조 방법은, 엿기름을 중량비 5배 이상의 냉수와 혼합하여 20분 이상 불린 후, 상기 불린 상태에서 엿기름을 주무른 후 엿기름을 거름망에 받치고,
