This study examined the characteristics of Sulgidduk with different amounts of apios powder (0, 10, 20, 30, and 40%). The moisture content of Sulgidduk significantly increased with the addition of apios powder. Also, the pH values of Sulgidduk significantly decreased with the addition of apios powder. The addition of apios powder in the Sulgidduk decreased the lightness (L) in Hunter’s color value, but increased the redness (a) and yellowness (b). By increasing the quantity of apios powder, the hardness, gumminess, and chewiness of Sulgidduk decreased and its springiness increased. The addition of apios powder in the Sulgidduk increased the total polyphenol content and DPPH-radical-scavenging activity. In the sensory evaluation, the addition of 20, 30% apios powder had the best score in taste and overall preference. This study suggests that apios powder is an excellent ingredient for improving the sensory preference and functionality of Sulgidduk. The study also shows that it was the addition of 30% apios powder can be used to make functional Sulgidduk.