Millimeter-Wave (mmWave) frequency bands have been importantly considered for 5G wireless communications. The mmWave band enables the use of a very wide spectrum to provide higher data rates and a better quality of wireless signals satisfying various multimedia services such as smart-phones, tablets, and wearable devices [1]. The mmWave 5G channel model will be newly established guidelines for modeling methodology and parameterization in various environments. Several papers about the channel capacity measurement have been introduced to demonstrate the effect of antenna polarization diversity in multiple-input multiple-output (MIMO) systems[2]-[3]. However, it is not appropriate that the studied results directly apply to the mmWave MIMO situation because they are based on the low frequency band below 6 GHz. Thus, it is necessary to newly investigate the effect of antenna polarization for mmWave MIMO communications. In this regard, we compare the channel performance of six cases of MIMO antennas with different polarizations in a reverberation chamber (RC).