The utility model discloses a device based on principle of osmosis produces mercury and bivalent mercury standard gas, including elemental mercury standard gas emergence system, it includes first carrier gas device of connecting in order through the pipeline and the elemental mercury generator that produces the mercury vapour body, includes still that bivalent mercury standard gas takes place the system, its bivalent mercury generator that includes the plasma gas source device who connects in order through the pipeline, gaseous premixer and production bivalent mercury gas, gaseous premixer still with the export of elemental mercury generator is connected for with the mercurous gas mixing of plasma air supply with the production of elemental mercury generator, the bivalent mercury generator is provided with high frequency and high voltage alternating current power supply generating device for producing plasma, be bivalent mercury with the mercury gas cyaniding gaseous, obtains elemental mercury standard gas and bivalent mercury standard gas simultaneously, adopts same mercury source, avoids adopting different mercury source need carry out the problem of tracing to the source for twice and transmitting, operating is simplified step because of the mercury source nonconformity.