The objective of this study was to evaluate the impact of xylanase supplementation on the digestibility of dietary energy (DE) with or without DDGS over three time points in growing pigs. The results showed xylanase supplementation had no effect on dry matter (DM) digestibility or DE after 8 days, had mixed effects on DM digestibility and DE depending on diet composition after 18 days, and improved DM digestibility and DE after 38 days. These results indicate that there may be an adaptation period necessary for a response to xylanase. Further laboratory analysis will provide insight into the mode of action of xylanase.