Studying investment opportunities and activities in animal production activity in general and red meat production in New Valley Governorate in particular is considered of great importance for many reasons, including the relative importance of the value of animal production, as it represents about 35.4% of the total value of agricultural production. The relative importance of the value of livestock meat, as it contributed about 58.7 billion pounds, representing about 27.8% of the value of animal production. The research aimed to (1) measure investment efficiency indicators for livestock fattening farms (calves and mixed cows) in the New Valley Governorate, according to farm capacity (number of heads). (2) Measuring the impact of potential changes in the most important economic variables for red meat production in New Valley Governorate (high costs, low returns, high costs and low returns together) on the efficiency of investment at the level of farm capacity. The research was based on a field sample of 60 farms for fattening mixed cow calves in New Valley Governorate, which were randomly drawn from the study population. The sample was classified into two categories according to the farm’s capacity, each category having 30 observations. The net present value (NPV), the internal rate of return (IRR), and the return-to-cost ratio (B/C) were calculated at the discount rate, which represents the opportunity cost of investing capital in society, as the most important indicators of investment efficiency for the fattening farms under study. At the level of farm capacity, and according to the mathematical formulation of the discounted measures of the project value, according to the current operating conditions and according to sensitivity analysis. The research reached several results, the most important of which are: (1) Investment efficiency for fattening projects for fattening mixed cow calves in New Valley Governorate under the current operating conditions, where the value of the present net wealth amounted to about 837.12 and 2179.52 thousand pounds for farms of the two categories, small and large capacity, respectively. The internal rate of return also reached About 57% and 72% for small and large capacity farms, respectively. (2) Continuing to achieve investment efficiency for fattening projects for mixed cow calves in the New Valley Governorate, under conditions of risk of rising costs and declining revenues by 10% for each of them separately while holding the other constant, and in light of rising costs and declining revenues by 10% for both of them together at the same time. This indicates the feasibility and safety of investing in this activity. The research ended with a recommendation and implementation mechanisms that may help advance this sector and overcome the problems it faces.