Thermo-economic optimizations along with a detailed parametric analysis of an irreversible regenerative Brayton cycle with finite heat capacity of external reservoirs have been carried out. The external irreversibilities due to finite temperature difference and internal irreversibilities due to fluid friction losses in compressor/turbine, regenerative heat loss, and pressure loss are included in the analysis. The thermoeconomic function is the ratio of power output to the sum of annual investment, energy consumption and maintenance cost. The optimization of the objective function is done for maximizing the power output and thermal efficiency of the model. A detailed analysis on the efficiency of turbine and compressor, effectiveness of various heat exchangers, heat source inlet temperature and pressure drop irreversibility on power, efficiency and economic function has been carried out. Parametric analysis shows that turbine efficiency has more effect on the performance of model than compressor efficiency for the same set of operating conditions. The model analyzed in this paper gives lower values of various performance parameters as expected and replicates the results of an irreversible regenerative Brayton cycle model discussed in the literature at pressure recovery coefficients of α1=α2=1.