The aquaculture industry is one of the fastest-growing sectors in the food industry. The Nile tilapia, Oreochromis niloticus, is an important and inexpensive species of fish. A study was conducted to determine the effects of divergent dietary crude proteins on fish growth performance and antibiotic susceptibility of bacterial pathogens infecting all-male tilapia (Oreochromis niloticus). Forty-eight fish samples were grouped into three groups based on crude protein percentages, including 15%, 30%, and 45%, and the fish's body weight and length were measured on days 15, 30, 45, and 60. Ordinary one-way ANOVA (Tukey's multiple comparison test) was applied to three divergent dietary crude protein groups for the examination of growth performance at different time points. Using the same fish samples, bacterial strains were isolated from fish skin and gills and identified based on their morphological characteristics and biochemical testing. Kirby Bauer's disc diffusion method was used to determine the antibiotic susceptibility of identified bacterial isolates. The ANOVA (Tukey's multiple comparison test) results showed that 45% crude protein level in fish feed led to a greater growth rate than 15% and 30% under high-performance conditions. The antibiotic susceptibility findings indicate that Staphylococcus aureus showed the highest sensitivity (50%) toward antibiotics while Pseudomonas aeruginosa showed the least susceptibility (10%). The study provides a new perspective on the impact of crude protein on fish growth performance, as well as baseline information for the management of fish diseases based on antibiotic sensitivity.