Abstract: Four hundred and twenty growing broiler-chicks (3–6 weeks of age) were used in the experiment to assess the effect of replacing groundnut cake (GNC) with either cooked jack bean meal (CJBM) or roasted devil bean meal (RDBM) on the growth characteristics, blood, total serum and liver proteins. Seven diets were used for the trial. Diet 1 contained 150 gkg-1 groundnut cakes and this was replaced in diets 2, 3 & 4 with CJBM at 5, 10 & 15% while it was replaced in diets 5, 6 & 7 with RDBM. The birds were fed their dietary treatments for 21 days. The results showed that the average final live weight of birds fed CJBM and RDBM decreased respectively with 17.7 – 34.5% and 3.7 – 7.2% of the weight of those fed on the control. The average weekly weight gain and average feed consumption decreased with increased level of GNC substitution with CJBM and RDBM. The N- retained by birds fed the control diet and those on 5% CJBM and 10% RDBM – based diets were identical while the N- retained was lowest in bird fed 15% CJBM – based diet. Of all the organs measured only the relative weight of the gizzards was significantly (P<0.5) influenced by the dietary treatment. Also, the blood variables, serum and liver metabolites measured were not significantly (P<0.05) influenced by the dietary treatment. It was concluded that while CJBM could only be included at not more than 100 gkg-1, the RDBM could be included even more than 150 gkg-1 of the diets for broilers. The use of these lesser-known legumes in the feeding of broilers in the third world countries, if properly harnessed and processed, will enhance broiler production and consumption among the poor populace.