We characterized the partially defatted baru flour (PDBF), a byproduct of the extraction of baru oil, and evaluated its use to produce cookies. Analyzes of composition, total phenolics (TP), total flavonoids (TF), condensed tannins (CT) and antioxidant activity (AA) were performed. Cookies were prepared with 5 levels of replacement of wheat flour (WF) by PDBF, and compared for antioxidants, texture and acceptance. PDBF presented more proteins (29.46 g/100 g), lipids (11.84 g/100 g), fibers (38.80 g/100 g), but fewer carbohydrates (11.57 g/100 g) than WF. PDBF can be labeled as rich in iron, zinc and cooper. TP (121.34 mg/100 g) were intermediate to levels found in baru almonds and other nuts. TF (85.41 mg/100 g) was higher than in nuts. CT (64.39 mg/100 g) were close to values known for wines and walnuts but lower than in other nuts. AA was comparable to many tropical fruits. Hardness and fracturability of cookies increased starting from 75 g/100 g PDBF. Acceptance of cookies with 25 g/100 g PDBF was comparable to WF cookies, for some attributes and one group of consumers. Besides the impact on acceptance, the replacement of WF for PDBF influenced positively on nutritional and antioxidant characteristics of cookies. •Baru flour showed high fibers, lipids, iron, cooper, zinc and low carbohydrates.•Baru flour presented antioxidants' contents comparable to those of known sources.•Hardness and fracturability increased in cookies from 75 g/100 g of baru flour.•Replacement of 25 g/100 g of baru flour led to acceptance close to control cookie.