Nowadays, the usage of wireless devices is increasing rapidly along with the amount of data consumption, user demands, and their expectations. Because of this, new technologies have proposed, including millimetre wave (mmWave) spectrum for large bandwidths, multiple input and multiple output (MIMO) for massive connectivity, and extreme mobile broadband (eMBB) for high data rates and low latency. Mobile network operators (MNO) around the world started deploying 5G networks in mid-frequency bands (i.e. 3–6 GHz) with existing 4G cellular networks. However, the high-frequency bands (i.e. 24 GHz–100 GHz) can offer a wider spectrum (i.e. 400~800 MHz), which is needed to meet the ever-growing capacity demands, highest bitrates (~20 Gb/s), and lowest latencies. While millimeter waves have the advantage to offer broader bandwidth and high spatial resolution, they cannot travel long distance due to their highly attenuation nature and are easily prone to interference, absorption and weather conditions. Beamforming and antenna modelling are some strategies that can improve cell coverage and capacity, as well as spectral efficiency of the network. Thus, the main objective of this thesis is Performance Comparison of Antenna models for 5G Beamforming. A downlink massive MIO sustem operating at mmWave have been considered to analyze antenna beamforming model. Specifically, two 5G antenna beamforming models such as Katheirn 742212 antenna and AAU5613 antenna are compared with 3GPP antenna model. The simulation results show that, the proposed beamforming antenna model outperforms the conventional 3GPP antenna model. Besides, the performance of two massive MIMO precoding techniques Zero Forcing and Maximum Ratio Transmission has been evaluated at the proposed antenna model. The results show that the proposed antenna beamforming have given optimal performance for mmWave massive MIMO systems. Keywords: Beamforming, mmWave, Antenna models, and Precoding.