Abstract: Along with the propose of the strategy of building power grid with ’three functions and two networks’ and developing ubiquitous Internet of Things, the power system terminals are widely interconnected and ubiquitous, so the terminals are often regarded as the target and springboard when power grid is attacked. Under this background, by focusing on the security interconnection of smart devices and demand of mobile operation in power system, this paper expounds the challenges and technical framework of the security protection for smart terminals of power system. This paper builds the protection framework for smart terminals of power system covering chip layer, terminal layer and interaction layer. This paper gives a detailed prospect for some key technologies, such as provable security protection in chip circuit layer and kernel fault self-recovery, active immunity of heterogeneous terminals integrating trusted computing and business security, precise perception and blocking of terminal threats with uncertain attack features, power terminal security access and business isolation in the terminal interconnection computation environment.