Communications service current increases and needed allocation ribbon great frequency. Ka-band (Kurtz-above band) is the microwave band of the electromagnetic spectrum range between 26 GHz% u2013 40 GHz. Ka-band used on the satellite communication system is a 20 GHz (Downlink) and 30 GHz (Uplink). However, in tropical conditions such as Indonesia where the intensity of rainfall is high enough can cause the condition of the satellite communication systems will be muffled on the side of the receiver. One of the methods to overcome the impact of the rain attenuation are site diversity. Site diversity method is a method to the process of transmission of satellite ka-band to more than one earth station location. So the transmission signal communication will use the link that has the smallest rain attenuation which aims to guarantee that the rain attenuation occurs at the location of the first Earth station is not greater than the second Earth station location, and vice versa. Earth station locations used was the Perak station and Juanda station. The purpose of the use of site diversity for improving the signal to noise ratio (SNR). Application of the method of site diversity in satellite communication system resulted in the band ka-improved performance when compared to the communication systems communication systems without site diversity. It can be seen on probability 0,1 % SNR value on links with condition of Perak station downlink 4,349 db and uplink 0,09804 db, while using a technique selection combining produce the condition of SNR downlink 10,31 db and uplink 25,15 db.