This study aimed to evaluate the effects of substituting varying levels of a plant protein mixture (PPM) with freshwater shrimp meal (FSM) on the growth, digestibility, and economic returns of Nile tilapia. Monosex male O. niloticus fingerlings (initial mean body weight, 28 ±0.01 g) were simultaneously cultured in cages installed in an earthen pond (for growth and economic returns studies) and tanks (for apparent digestibility assessment) for a period of 180 and 60 days, respectively. The PPM was made of 50% soybean meal, 25% sunflower cake, and 25% cotton seed cake. Replacement of FSM was done at 25%, 50%, 75% and 100% of the dietary protein and the diets labelled D1, D2, D3 and D4, respectively. The test diets were compared with a control diet containing (D0, 0% PPM). After 6 months of feeding, the fish fed on diets D0 and D1 did not differ (p >0.05) in growth performance. Fish weight gain decreased significantly (p <0.05) as the levels of PPM increased. Apparent digestibility of crude protein decreased significantly (p<0.05) with increasing inclusion levels of PPM in the diets with diet D0 recording the highest digestibility followed by D1 and D2 although D0, D1 and D2 were not significantly different from each other (p >0.05). Diet D0 and D1 were not significantly different (p>0.05) hence cost benefit analysis showed that D1 was economically viable than D0. In conclusion, PPM could partially replace FSM up to 25% without adverse effects on growth performance.