High gain, low sidelobe and backlobe levels are important parameters in the reflector antenna design. These parameters are being vital important for the antennas used in radar systems, especially in military applications. If the design of the reflector is made without considering the implemantation stage, the characteristics mentioned above can not be provided. To manage this performance reduction, some improvements should be added to the design in the theoretical design stage. This paper propose two analysis for increasing the performance of a prime fed reflector antenna. The first analysis is choosing the true feedline mechanism and the second one is the effect of shroud usage. These analysis are made for an X-band waveguide fed prime focus reflector antenna. Numerical results and chosen design configuration are also presented in the numerical results section. © 2011 IEEE.