Mealworm is the most widely used edible insect in Korean traditional food. In this study, the quality characteristics and antioxidant activity of Garaedduk containing different proportions of powdered mealworm (0%, 3%, 6%, 9%, and 12%) were evaluated in order to enhance the utilization of mealworm. The results revealed that moisture content decreased while pH and starch elution increased, with increasing amount of mealworm. Furthermore, the amount of total amino acids, essential amino acids, and non-essential amino acids increased with increasing amount of mealworm. Regarding chromaticity, the L value decreased while the a and b values increased as the amount of mealworm increased. The addition of 6% mealworm showed slight differences in the pore size and surface smoothness as compared to plain Garaedduk. Texture, hardness, chewiness, and gumminess increased, but cohesiveness decreased with increasing amount of mealworm. The preference test evaluating the appearance, flavor, taste, texture, and overall preference showed that 6% mealworm additive group had the highest preference. In addition, antioxidant activity of the newly developed Garaedduk increased with increasing amount of mealworm. In conclusion, Garaedduk enriched with 6% mealworm showed promising results for developing rice cake with improved nutrition and antioxidant activity and excellent overall preference and quality.