The response to the inclusion of common vetch (Vicia sativa cv. Morava) at levels up to 225 g/kg diet was evaluated in growing pigs between 91 and 161 days of age. A total of 312 male pigs, selected at a liveweight of 37.6 ± 0.24 kg, were group housed in pens of 19–20 pigs, each initially in commercial grower facilities, which were then split within treatment into pens of 9–10 pigs in commercial finisher facilities. Pens were randomly allocated to 1 of 4 diets, 4 pens per diet. Vetch replaced peas in the wheat-based, protein-adequate diets at levels of 0, 75, 150 and 225 g/kg diet, with the digestible energy and lysine levels being similar for each diet. Pigs were offered the experimental grower diets for 4 weeks, followed by the corresponding experimental finisher diet for 6 weeks. Growth performance was not significantly affected by level of vetch up to 225 g/kg during the first 4 weeks of feeding with average growth rate, feed intake and feed conversion efficiency being 871.5 g/day, 1.90 kg/day, and 2.20 kg feed/kg gain, respectively. However, a significant negative linear response was observed for feed intake in pigs between 119 and 161 days of age, which resulted in voluntary feed intake decreasing from 2.62 to 2.44 kg/day when inclusion of Morava vetch increased from 0 to 225 g/kg. A significant curvilinear response was also observed in growth rate and feed conversion ratio during this period. These significant effects during the later growth phase resulted in significant decreases in voluntary feed intake and growth rate from 2.34 to 2.17 kg/day, and from 948 to 873 g/day, respectively, for the entire growth period as Morava vetch was increased from 0 to 225 g/kg diet. Thus, it is suggested that Morava vetch could be fed at rates up to 225 g/kg for pigs between 91 and 119 days of age, but should be reduced to less than 150 g/kg if feeding continues beyond 119 days of age.