The surge in the price of soybean in the domestic and international market has led to a hunt for a potential alternative for protein sources in poultry feed. Silkworm pupa is a rich nutrient reservoir of fats, protein, minerals, essential amino acids, etc., which is underutilized for its potential nutritional applications. Despite its rich nutritional value, it is considered a waste and discarded unscientifically resulting in serious environmental concerns. Therefore, in the present study De-oiled Silkworm Pupa Cake (DOSPC) rich in protein (64.88%), obtained from defatting the discarded silkworm pupa through a pilot-scale Supercritical Fluid Extraction technology, was used as a sustainable alternative to soya bean meal in poultry feed. For the present study, 1500 numbers of broiler chicks (day old chicks) of COBB variety were selected and divided into 5 experimental groups and 10 replicates per group with 30 birds per replicate, which were fed in amounts of Control Diet comprising 100% Soyabean meal and 0% DOSPC(Group 1), Diet with 25% DOSPC and 75% Soyabean meal (Group 2), Diet with 50% DOSPC and 50% Soyabean meal (Group 3), Diet with 75% DOSPC and 25% Soyabean meal (Group 4) and Diet with 100% DOSPC and 0% Soyabean meal (Group 5). Experimental trials were conducted for 6 weeks and details of average body weight gain, feed consumption, and FCR was collected for each week. The results from this study suggested that Soyabean meal can be replaced with DOSPC up to 50% and/or 75% for optimum FCR and Body weight gain in the birds. Both groups 3 and 4 reported similar output with no significant variation. Body weight gain of 2610 g/bird was observed in the treatment group 3 compared to the control group which was 2324 g/bird, FCR of 1.36 was observed in Group 3 which was significantly better than the FCR of the control group which was 1.52. The immunological assay against Newcastle Disease (ND) and Infectious Bursal Disease (IBD) revealed improved immune response in treatment groups supplemented with DOSPC in their feed. The organometry, histopathological, gut health and overall growth performance of the treatment group were on par with the control group and this suggested that replacement of Soyabean Meal with 50% and/or 75% is beneficial for poultry farming in terms of better nutritional intake for the birds and profitability for the poultry farmers.