—In this paper, we present mobile agent systems supporting persistency. In order to develop the mobile agent systems, a mobile agent framework has to have functions to support persistence of agents and persistence of an agent runtime environment. Our developed Java-based mobile agent framework named Maglog is taken up an example of a mobile agent framework. Maglog consists of three basic components, which are agents, agent servers and fields. Agent server and fields are corresponding to an agent runtime environment. The effectiveness of persistency is confirmed through descriptions of two mobile agent systems: a distributed e-Learning system and a scheduling arrangement system.