Two experiments were conducted, each with 80 broiler chickens allocated to four groups of 20 birds. All diets were wheat-based and isoproteinous. In Experiment 1, the diets were prepared with or without 300 g of white lupin cv. Bardo per kg; either soya oil (diets S and SL) or tallow (diets T and TL) was added to equalize crude fat content. In Experiment 2, diets were prepared with or without 200 g lupin/kg and were supplemented either with lard (diets L and LL) or rapeseed oil (diets R and RL) to be isoenergetic. In Experiment 1, starter diets were fed between days 8 and 36, from 22 to 28 days a balance trial was performed on 8 birds from each group. In Experiment 2, starter, grower and finisher diets were fed from days 10 to 46 of life. At the end of the experiment, 12 birds from each group were slaughtered and the fatty acid composition of lipids in breast muscles, hearts and abdominal fat pads was analysed by gas chromatography. In Experiment 1, the fat digestibility in diet T was 0.60, in diet TL 0.78 (P<0.05), however, performance was lower in the TL group (P<0.05). In Experiment 2 the performance of chickens did not differ among groups. In spite of the large differences in fatty acid composition of diets, oleic acid dominated in the lipids deposited in the body of all chickens, except those fed diet S. Inclusion of lupin into diets caused an increase in the concentration of oleic and α-linolenic acids, while, with the exception of group SL, it did not significantly affect the concentration of linoleic acid in broiler tissue lipids. Due to this, the n-6/n-3 PUFA ratio in broilers fed diets with lupin was lower than in the respective controls. White lupin seeds may be used as a source of α-linolenic acid in balanced chicken diets and may favourably modify the fatty acid composition of carcass lipids and thus the health attributes of broiler meat.