The Gaoyuzhuang Formation is a geologic formation in China. It preserves fossils dating back to the Calymmian period of the Mesoproterozoic. It is one of the first formations to preserve definitive macroscopic eukaryotes, at almost 1.6 billion years old. In addition to this, the site preserves a diverse microbiota with various cyanobacteria and fungus-like fossils known.