Background: Congenital duodenal obstruction occur with other anomalies in 50% of cases. Although predictable, its association with biliary/pancreatic anomalies is rarely reported. All cases of duodenal atresia (DA) and stenosis (DS) associated with biliary and/or pancreatic abnormalities were analyzed. : A systematic review searched all studies reporting association between DA/DS and biliary/pancreatic abnormalities. The study was performed according to PRISMA guidelines. Results: Of 522 studies reviewed, 285 were analyzed after removing the duplicates, and 104 (249 patients) meeting the inclusion criteria, were included. Anomalous bifurcated bile duct was described in 24 cases (20 DA, 4 DS): 6 at necropsy, and 20 at perinatal surgery. Choledochal cyst was found in 7 patients (5 DA, 2 DS): 1 perinatally, 2 in the first year, 4 at median age of 6.5 years (range 4-27 years). Biliary atresia was diagnosed perinatally in 13 patients with DA and in 1 at 9 months. Annular pancreas was discovered in 146 patients (15 DA, 113 DS, 18 not specified): 113 perinatally, 4 children, and 28 adults (median age 33 years, range 4-72 years). In the remaining 58 cases, a combination of biliary and pancreatic abnormalities was diagnosed in 41 DA, 16 DS, 1 not specified duodenal obstruction, in 35 patients perinatally, in 4 infants, and in 19 at median age of 3 years (range 1-40 years). Conclusions: Presence of DA/DS should rise the alert for a possible association with biliary/pancreatic abnormalities. Therefore, a careful intraoperative approach should be adopted when repairing DA/DS to avoid damaging biliary and pancreatic ducts. In addition, appropriate imaging looking for biliary/pancreatic anomalies should be considered in symptomatic patients.