Door-on-door for test box

The utility model discloses a door-on-door for a test box, which comprises a large box door connected with a test box body, and is characterized in that a sampling channel corresponding to a sample placing area of the test box body is arranged on the large box door, and a small box door capable of being opened and closed is arranged in the sampling channel. A control panel is further arranged on the front face of the large box door. Samples in the test box body can be quickly and conveniently taken out or replaced through the small box door under the condition that the large box door is not opened, meanwhile, the test environment in the test box cannot be quickly synchronized by the outside after the small box door is opened due to the fact that the small box door is small, and therefore when a next sample is tested, the test efficiency is greatly improved. A test environment in the test box can reach a value required by a test by taking a small amount of time, so that the test time for testing a plurality of