With　the　rapid　development　of　the　space-based　information　network,　the　network　coverage　has　been　further　expanded.　Many　areas　where　ground　infrastructure　is　difficult　to　deploy　can　be　accessed　via　satellite.　The　application　scope　of　the　Internet　of　things　has　been　greatly　expanded.　Ground　sensors　collect　data,　UAV　as　an　air　sink　node,　data　is　transmitted　to　the　Internet　through　satellite,　this　type　of　Internet　of　things　application　is　called　space-based　Internet　of　things.　In　space-based　Internet　of　things　applications,　the　communication　resources　are　more　valuable　and　the　data　transmission　link　is　more　unstable,　data　transmission　is　the　major　challenge　in　the　application　of　space-based　Internet　of　things.　With　the　capability　of　acquiring　reliable　communications,　Data　coding　plays　an　important　role　in　satellite　communications.　However,　the　usage　of　data　coding　in　space-based　Internet　of　Things　are　still　an　open　problem.　In　this　paper,　the　space-based　Internet　of　things　scenario　is　modeled,　and　a　layered　fountain　code　are　proposed　in　this　scenario.　Sensed　data　is　coded　and　collected　through　a　distributed　and　a　layered　approach,　which　is　suitable　to　the　space-based　Internet　of　Thing　applications.　Simulation　results　show　that　the　proposed　approach　can　guarantee　high　reliability　and　throughput　in　data　collection.　©　2020　IEEE.