Integrated satellite-terrestrial communications using low earth orbit (LEO) satellites for high data rate transmissions are expected to be incorporated in future wireless networks (e.g., in 6G and beyond). To this end, equipping LEO satellites with a large-scale antenna array in the context of massive multiple-input multiple-output (MIMO) has gained significant research interest both in academia and in industry. However, a fully digital implementation of MIMO signal processing for massive MIMO LEO satellites is not viable due to the high power and complexity requirements. To address this, hybrid antenna array architectures are proposed. This work considers fully-connected hybrid antenna array architecture and analyses the performance of hybrid beamforming (HBF) for massive MIMO LEO satellites. We consider two scenarios relating to the angular spread of user terminals (UTs) on the ground, i.e., small angular spread where UTs are uniformly distributed in a small coverage area, and large angular spread where UTs are uniformly distributed in a large coverage area. The sum rate performance of HBF in different scenarios of user angular spread, and channel state information is analysed and important insights are provided. The performance of HBF is also compared with the fully digital beamforming and analogonly beamforming.