Provided are an electric marketing service expansion mobile application system and a work method thereof. . Traditional managing software which can only be used in a local area network of an electric power company greatly restrains site communication and improvement of the service quality. The electric marketing service expansion mobile application system comprises an upper computer and a portable handheld set. The handheld set is provided with a wireless communication module, a task receiving module, a route planning module, a customer information inquiring module, a power grid information inquiring module, a service expansion processing module and a site data uploading module. The upper computer is provided with a BOSS professional system. The BOSS professional system is provided with a mobile operation platform module, a service expansion data receiving module and a work order processing module. The technical scheme of the electric marketing service expansion mobile application system changes an interactive traditional operation method of going back and forth between a site and the BOSS system for many times, achieves space extension and time expansion of marketing service expansion work and improves the work efficiency and the service level again.