Boutan's whiting, Sillago boutani, is a poorly understood species of coastal marine fish of the smelt-whiting family Sillaginidae that inhabits the waters of the Gulf of Tonkin and south eastern China. Like most sillaginids, the species inhabits areas populated with a number of other whiting species of similar appearance, causing the species to often be misidentified as the well known Sillago sihama, and for this reason its biology is poorly known. The species is taken by seine net in Vietnam and is often exported to Japan.