This paper describes the Smart Operation of Networked Appliances (SONA) system which realizes the autonomous and asynchronous operation of networked appliances by using mobile agents. In SONA system, the mobile agents operate networked appliances in place of user’s direct manipulation. Existing appliances operation systems such as remote controllers require users to input their demands synchronously with the appliances, while SONA system only requires users to input their demands in a lump once for all. To realize autonomous and asynchronous operation system, the SONA system is equipped with appliances lookup service, operation plan composer, and mobile agent system. In this paper, we present the design, implementation, and evaluation of SONA system.