PURPOSE: To assess the effects of Roux-en-Y jejunal limb length on gastric emptying and enterogastric reflux. METHODS: Seventy male Wistar rats were submitted to antrectomy with Roux-en-Y reconstruction and then were divided into two groups of 35 animals. Group A, short limb (7.5 cm) and Group B, standard limb (15 cm). Group A and B were subdivided into five subgroups each in order to study enterogastric reflux at 30 and 60 minutes and to evaluate gastric emptying at 5, 10 and 15 minutes. In order to measure gastric emptying and enterogastric reflux, radiotracers 99m Tc-Phytate and 99m Tc-DISIDA were respectively used. RESULTS: For gastric emptying, the radiotracer concentration was lower in Group A than in Group B after five minutes. The enterogastric reflux was present, but there were no significant differences between enterogastric reflux indexes concerning both A and B Groups. CONCLUSION: A standard Roux limb, besides being unable to protect the stomach from the enterogastric reflux, may become a functional barrier for gastric emptying.