This study has investigated the physicochemical and sensory characteristics of muffins supplemented with 0%, 5%, 10%, 15%, and 20% roasted safflower seed powder (SSP) in order to assess its applicability as a functional ingredient in baked goods. As the SSP content increased, the pH of both the batter and the muffins significantly decreased, whereas the height, volume, and specific volume of the muffins increased. Moisture content and baking loss rate were not significantly affected. Color analysis revealed that the L* and b* values decreased, whereas the a* values and total color difference (ΔE) significantly increased with higher SSP levels. Texture profile analysis showed that the hardness, gumminess, chewiness, and resilience decreased as SSP increased, whereas springiness improved. In the sensory evaluation, the overall preference was highest for the control (7.30), followed by the SSP 15 group (5.77), thus indicating that excessive SSP addition negatively affected consumer acceptance due to a darker color and rougher texture. However, the SSP 15 formulation achieved a favorable balance between health functionality and sensory quality. These results suggest that up to 15% SSP can be effectively incorporated into muffins in order to improve their functional value without compromising product quality or consumer satisfaction.