The invention discloses a spatial expandable ground plane device, comprising folding ring rods, ring rod connecting joints, folding rib rods, rib rod connecting joints, ring-rib connecting joints and rib frame connecting joints. The folding ring rods and the folding rib rods can be expanded from a vertical furled state to a horizontal working state through the ring rod connecting joints and the rib rod connecting joints. The ring-rib connecting joints and the rib frame connecting joints connect a ring structure with a rib structure to become a furled/expanded integral structure. A wire mesh or an aluminum-plated thin film is bound with the integral structure, so as to form the spatial expandable ground plane device. In a bound furled state, torsion springs in the ring rod connecting joints and the rib rod connecting joints store elastic potential energy; after binding is removed, the elastic potential energy of the torsion springs is transformed into driving energy so as to drive the ring rods and the rib rods to be expanded and locked automatically. The device has excellent comprehensive performance indexes of low surface density, high configuration precision and high ingathering rate, which can be used as an expandable support device in outer space or on ground.