A medical tested object auto-ejection structure comprises a detection instrument and a tested object (1). An insertion port is formed in the detection instrument. When the tested object (1) is inserted in the instrument through the insertion port, the bottom end of the tested object (1) presses a bulge (21) used for rebounding, and a raised step (11) arranged on the surface of one side of the tested object (1) is locked on a clamping buckle (31) arranged at a position corresponding to the step on the instrument simultaneously, and after a test is finished, the instrument releases the locking of the clamping buckle (31) for the tested object (1) by a transmission device, and the tested object (1) is ejected from the instrument in time under the action of the bulge (21) used for rebounding, thus solving the problem of forgetting to pull the tested object out or inability to pull it out in time, and improving the reliability of the product.