The embodiment of the invention discloses a standard gas acquisition device. The acquisition device is characterized by comprising a compressed gas bottle connector, a washing gas bottle and a pressure reduction valve, wherein the washing gas bottle is filled with background gas; the compressed gas connector comprises a tee joint pipe with a first connector, a second connector and a third connector; the first connector can be connected with the bottleneck of a compressed gas bottle filled with standard gas; the second connector is connected with the bottleneck of the washing gas bottle; and the third connector is connected with an inlet of the pressure reduction valve. When the background gas blows impurities in a dead volume till the impurity content is lower than a predicted value, the standard gas is acquired through the standard gas acquisition device, so that on the premises of not lowering the standard gas utilization ratio and needing less standard gas sample quantity, the residual impurities in the dead volume can be cleaned effectively.