The study carried out an investigation for a drilling core of the Silurian System in Fengxiang town, Yichang, Hubei Province. 313 samples were collected from about 100mlong core consisting of the Lower Member and the lower Upper Member of Silurian Longmaxi Formation. Among them, 165 samples of black shales and dark mudstones produce wellpreserved Early Silurian chitinozoans. Four chitinozoan biozones were recognized, which include Belonechitina? postrobusta, Conochitina alargada, Armoricochitina sp. nov. and Conochitina emmastensis biozones in an ascending order. Each chitinozoan biozone was diverse and includes new species occurring with well known species, and can be correlated with chitinozoan biozones found from the contemporary strata of the Latvia, Estonia and other areas. The relationships between the chitinozoan biozones and the graptolite in the Silurian of the Yichang area indicate that the FAD of the chitinozoan Conochitina alargada is the same as that of the graptolite Monograptus triangularis, and can be regarded as one of the biomarks which defined the basal boundary of the Aeronian stage.