Abstract: The conceptual design of a small modular reactor (SMR) integrated with alkali metal thermal to electric converter (AMTEC) units, called SMR-AMTEC system, was proposed internationally in order to meet the reliability in power supplies subjected to extremes of operating conditions. Three key technologies of the small modular reactor in the conceptual design were developed in the paper. They were reactor core physical control technology based on rotating drums, this primary loop natural circulation technology under normal power and the heat removal technology based on natural circulation. The preparation technologies of three key components of the small multi-tube circulating AMTEC unit coupled with the conceptual design were particularly developed. They were fabrication technology of porous TiN film electrode of AMTEC, the sealing technology of BASE (Beta″alumina solid electrolytes) components and the development and test technologies of wick components. The feasibility of the SMR-AMTEC system is preliminarily verified through R&D of the technologies above.