This study investigated the effects of dietary lupin (LP) as a replacement for soybean meal (SBM) on the performance, meat quality, and blood parameters of broilers. A total of 960 1-day-old Ross 708 broilers were divided into four dietary groups. The four diets were formulated with different levels of dehulled LP content in place of SBM; LP0: 0, LP50: 50, LP100: 100, and LP200: 200 g/kg. There was a trend ( P < 0.10) for reduced weight gain in the LP200 group compared with other groups. The feed conversion ratio was higher ( P < 0.05) in the LP200 group than in the LP0 and LP50 groups. Concerning breast meat characteristics, the lightness color (L*) was lower ( P < 0.05) in the LP200-fed group compared with the LP0 group. Polyunsaturated fatty acids were higher ( P < 0.05) in LP100- and LP200-fed chickens than in LP0-fed chickens. Serum HDL cholesterol was significantly ( P < 0.05) higher in the group fed LP200 compared with the groups fed LP0 and LP50. A higher serum concentration of interleukin (IL)-2 was found in groups fed LP100 and LP200 than in groups fed LP0 and LP50. Our results suggest that LP could be a dose-dependent SBM substitute, and that the optimal level of LP inclusion is approximately 100 g/kg.