The rapid development of internet technology and mobile communication technology has brought significant changes to the way in which people retrieve information and experience application service. We believe that application migration can perfectly solve these problems, if the continuity of application service experience and efficiency of migration process is guaranteed. This paper firstly proposes a general model of the application migration in the virtualization environment and then designs the migration mechanism based on memory pre-synchronization. We also present memory change probabilistic prediction and slow-start synchronization adaptive policy which are used to reduce the pressure on the network and application performance loss. Lastly, we implement the above methods on KVM. The experiment results show that the process of 256MB guest ram can be accomplished within 1 second after we launch the migration whereas the original one takes at least 7 seconds on the network of 1Gbps. The transmission quantity during the synchronization decreases by 50.5%, 63.9% and 65.6% on text editing application, audio application and movie application respectively.