Abstract: The dissimilar materials joint performances, such as strength, high-temperature performance and thermal shock resistance, are damaged by thermal stress seriously. Selecting or designing a suitable interlayer is an effective way to reduce the thermal stress of dissimilar materials joints. The stress relaxing principles and the basic structure types of dissimilar materials joints interlayer are introduced. The current research situation is summarized especially of multi-layer interlayer, energy absorption mezzanine interlayer, composites interlayer and functionally gradient interlayer. The advantages and disadvantages of each interlayer are also commented. Overall considering complexity, economy, connection quality and adaptiveness for material connection technology, composites interlayer and energy absorption mezzanine interlayer are of most future.