Abstract: In order to solve the problem of quantum satellite communications handover in LEO (Low Earth Orbit), the algorithm of quantum satellite communication handover in low earth orbit based on entanglement degree computing was proposed. After the influence of the distance of quantum satellite and the mobile terminal and quantum noise ,this algorithm obtained the entanglement of two subsystems when environment having the quantum decoherence in quantum systems and always choose the satellite which have the maximal entangled degree to complete real-time handover. Simulation results show that the handover success rate of this algorithm can be achieved more than 95% in both 700km and 1400km with some entanglement dgree,and it is important that can achieve smooth handover of quantum satellite. It has important supporting role in building the future global quantum communication system and its development of standards.

Key words: quantum optics, algorithm of satellite communication handover, entanglement degree, handover success rate