In the design and development of high confidence software, the software fault tolerance is one of the techniques to improve the credibility of the system. Fault tolerance is the ability of software to guarantee the service when the fault occurs. And a processing method for fault tolerance is to rely on redundancy technology. Based on the analysis of the structural redundancy and its influence on the credibility of the system, this paper proposes a redundancy mechanism for the core components of the component-based trusted software. The redundancy structure includes dual redundant structure for single component and composite components, 2 out of 3 redundant structure and its extension. And the fault detection and the judgment method are given. At the same time, the reliability of the system is analyzed on the basis of various redundant structures.