Technical Abstract: Polyphenolic compounds contribute to the antioxidant properties of blueberries. Due to limited availability of fresh fruit, blueberries are commonly preserved by canning and freezing, and used for baking. Unfortunately, the effect of these treatments on polyphenolic content and antioxidant capacity of the fruit are unknown. Our objective was to compare the polyphenolic content and antioxidant capacity of fresh, canned, and frozen berries, and pies prepared from canned and frozen berries. Pies were prepared using prepackaged pie crusts with either blueberries canned in water or frozen blueberries. The polyphenolic content (chlorogenic acid, flavonols, anthocyanins) determined by HPLC and oxygen radical absorbing capacity (ORAC) of all processed samples were compared to that of fresh berries. Blueberries canned in water and pie made from blueberries canned in water had comparable anthocyanin levels as fresh berries, but frozen blueberries and pies made from frozen blueberries, had 17% and 23% lower anthocyanins than fresh berries. The frozen berries had comparable levels of total flavonols as fresh berries, but the blueberries canned in water, pies made from blueberries canned in water or from frozen blueberries, had a 14% to 20% loss of total flavonols compared to fresh berries. Blueberries canned in water had comparable levels of chlorogenic acid and ORAC values as fresh berries, whereas pies made from blueberries canned in water or from frozen blueberries had a 10% loss in chlorogenic acid. ORAC values for frozen berries, pies made from blueberries canned in water or from frozen blueberries decreased 11%, 14%, and 26%, respectively compared to fresh berries. Antioxidant-rich polyphenolics were well retained in canned blueberries, but freezing and baking result in moderate losses. Although different forms of processed blueberries have lower levels of polyphenolics and antioxidant capacity than fresh berries, they are still a good and readily available source of dietary antioxidants.