Index fossil application is used to display the information of index fossils with important stratigraphic correlation and subdivision significance. It aims to provide the scholars that engaged in stratigraphic and paleontological research with query and retrieval services of the index fossils or provide an educational platform for the general public. The application now contains the information of 17 fossil groups from the Cambrian to Permian in the Paleozoic. The data mainly includes systematics, horizon, age, locality, preservation information, literature, and so on. Meanwhile, the platform currently provides three retrieval methods, fuzzy retrieval, geological age retrieval, and systematic classification retrieval.