PROBLEM TO BE SOLVED: To provide a manufacturing method of a sweet potato processed food, which allows the taste to be adjusted by imparting natural sweetness and sourness to heat-treated sweet potatoes such as steamed potatoes and baked potatoes without use of additives such as a sweetener and an acidulant; and a sweet potato processed food manufactured by the method.SOLUTION: A grain malt with an addition ratio of 2 to 30 wt.% was blended with heat-treated sweet potatoes, and the sweet potatoes are glycosylated at 50 to 70°C for 15 to 24 hours. The grain malt is a rice malt produced from yellow aspergillus as seed malt.