LEO is Low Earth Orbit satellite.It circulates on a lower orbit in a shorter period . Additionally LEO systems try to ensure a high elevation for every spot of the earth to provide a highquality communication link . The networks will play an important role in the evolving information infrastructure . It provides communication with shorter endto- end delays and e_ciency frequency usages . Some problems need to be solved before LEO satellite system can be successfully deployed . One of these problems is handover management . Even though LEO is an big invention in the 21st century mobile satellite comunication.