The aim of the study was to investigate the effect of the particle size of full-fat rapeseed and of multi-carbohydrase enzyme supplementation on chicken performance. The experiment was conducted with 480 male broiler chickens, divided into four dietary treatments, 15 replications with 8 birds each. Two basal diets were prepared containing fine-ground (FG) or coarse-ground (CG) rapeseed. Diets were unsupplemented or supplemented with a multi-carbohydrase enzyme preparation. The CG rapeseed depressed (P<0.05) body weight gain and feed conversion ratio (P<0.05) in comparison with FG. Birds consuming diets supplemented with multi-carbohydrase enzymes had a higher feed intake and body weight gain and a better feed conversion ratio during the first 2 weeks of life (P<0.05). During the first 14 days of life, fine grinding of rapeseed had positive effects on nitrogen retention (55.7 vs 50.8%), total tract digestibility of crude fat (70.4 vs 38.9%), and AME_N value (P<0.05). It can be concluded that fine grinding may be used to improve the nutritional value of full-fat rapeseed in broilers.