Background: The aim of this study was to evaluate, at 90 days, the adipose tissue in young male rats fed with flaxseed flour during lactation or during post weaning period. Methods: At birth, Wistar rats were assigned to two groups, whose dams fed with control (C) or flaxseed flour (F) diet during lactation. At 21 day, pups were weaned and fed control (CC and FC) or experimental diet containing flaxseed flour (CF). At 90 days, food and energy intake, body mass and length, body fat composition by dual-energy X-ray absorptiometry, leptin, insulin and intra-abdominal fat were analysed. Results: CF showed (P < 0.05): Higher body mass, leptin, mesenteric and epididymal (vs. CC) fat mass. FC showed (P < 0.05): Lower total and trunk fat mass, intra-abdominal (vs. CF), retroperitoneal (vs. CC) fat mass and adipocyte area (vs. CF). Conclusion: Flaxseed flour, during lactation period, contributes to lower intra-abdominal adiposity in young life.