Abstract: The space information processing systems based VLSI are easily suffered by SEU (Single Event Upset) .TMR (Three Module Redundancy) based structure redundancy and EDAC (Error Detection and Correction) based information redundancy are two kinds of system level faulttolerance methods for SEU. These methods are widely used in space aircraft electronic system. Simulation and analysis are implemented from four aspects: reliability, storage resource, hardware implement spending and time delay. The results show that EDAC is efficient when the data is long, the storage resource is limited and the demand of realtime performance is not high, however the TMR is efficient when the data is short, the storage resource is enough and the desire of realtime performance is high.