For satellite communications terminals, this paper deals with the design of a Micro strip Patch Array Antenna for KU-band applications that resonates at 12.3 GHz respectively. The substrate used for design is ARLON AD300N and the software used for simulation is Agilent ADS Momentum. This design expressed the array antenna in 8-element.It approach their corresponding results are validated based on their antenna parameters like VSWR, gain, directivity and power radiated and so on. One of the microstrip antennas (MSA) arrays achieved a radiation efficiency of 100%, which is among the best reported efficiencies for this resonating frequency and class of antennas.