Abstract: Feeding trial was conducted using 150 birds of day-old Anak broiler chicks, to assess the optimal level of quantitative replacement of soybean meal with raw sword bean meal in broiler diets. Thirty and Ten birds, respectively constitute a treatment and a replicate. Five experimental diets were formulated. Diet one was soybean based (control), while the test feedstuff quantitatively replaced 5, 10, 15 and 20% soy bean in diets 2, 3, 4 and 5, respectively. The birds were assigned to these diets; feed and water were given ad-libitum throughout the experiment. This experiment lasted for 28 days. Feeds given daily were recorded and feed intake and weight gain determined weekly. Data on carcass quality, organ weight, blood constituents and histopathology were obtained. They were subjected to analysis of variance and means were separated using New Duncan’s multiple range tests. There was significant (p<0.05) difference between the treatment means for all the parameters considered. Broiler chickens placed on the test-diets had severely hindered growth that was significantly (p<0.05) different from the results obtained from control diet. Feed-intake values were (43.3333, 31.8567, 25.5267, 19.0133, 16.7367), weight gain (20.3233, 14.4067, 10.34, 5.3933, 2.9990) and the feed conversion ratio (2.1367, 2.2033, 2.4467, 3.5700 and 5.6067). The gross margin of the control diet was higher (137.67) than the test diets (135.59, 106.61) (84.66, 66.88). Values of cut-parts showed significant differences in all parameters considered, with the birds placed on the control diet on the average performing better than others. Organ-weights showed significant (p<0.05) differences between the treatment means of the control diet and the test diets for all the parameters considered with the exception of the spleen. The values for heart intestine, proventriculus and gizzard followed no specific pattern that could be attributed to the effects of the diets, while the values for liver and kidney did. The liver values for the test diets became significantly higher than the control diet from diet 3 and above. The values for kidney for the test diets were numerically higher and became significantly (p<0.05) higher than the control diet for 15 and 20% diets. The principal effects of dietary raw sword bean on blood constituents were decreased RBC, abnormal MCH, MCV and MCHC when compared with normal range of haematological indices for broiler chickens. Also, there was increase in serum creatinine, alkaline-phosphatase and urea values. The inclusion of raw sword bean in the broiler chicken diets produce histopathological changes within the liver, kidney and spleen. Raw sword bean could not replace soybean meal quantitatively even at 5% dietary level of inclusion for starter broiler chickens.