The invention provides an on-orbit reconfigurable extensible satellite system and belongs to the technical field of spacecraft configuration. The on-orbit reconfigurable extensible satellite system ischaracterized by being on-orbit reconfigurable, on-orbit extensible, equipment-replaceable, adaptable to multi-type loading and the like. The on-orbit reconfigurable extensible satellite system comprises a satellite foundation platform, an extension truss and propelling control module cabins. A subdivision design is adopted by the satellite foundation platform. The satellite foundation platform comprises a propelling cabin, an equipment cabin and a loading cabin. Each cabin segment is connected through cabin segment butt joint interfaces, and thus cabin segment-level replacement and extensioncan be conducted. Octahedron configuration is adopted by the equipment cabin and the loading cabin. On-orbit replaceable equipment is installed on four of the surfaces of the equipment cabin, and on-orbit extensible interfaces are designed in the other four surfaces of the equipment cabin and used for on-orbit extension of the satellite system. Loading-generalized installation interfaces are distributed and arranged on the top surface of the loading cabin and applicable to multi-type loading. The extension truss and the propelling control module cabins are used for on-orbit extension of a whole spacecraft system by which large-scale loading application requirements are met and launched into orbit by transportation aircrafts as required.