The type of dehydration tube is one of the key factors influencing the dehydration technology of filling. The paper analyzes the water absorption model of plant roots, designs new dehydration tube and related test devices based on bionics, studies the dehydration efficiency, effect of the new dehydration tube and the dehydration law of unclassified tailings non-cemented filling. The test results show that the root-like design of the dehydration tube can increase the water passing area and reduce the seepage distance of the dehydration tube. Compared with the ordinary dehydration tube, the new type reduces the dehydration time by 20%, and the cumulative dehydration volume increases by 10.3%, which improves the dehydration efficiency. The tailings loss was introduced to evaluate the dehydration effect of dehydration tube, and the new type dehydration tube has a 45% reduction in tailings loss compared to the conventional dehydrating tube. The unclassified tailings non-cemented filling and the inner surface of the test device form a large number of uniformly distributed pore water-conducting zones, which is one of the reasons why the new dehydration tube can improve the dehydration efficiency. The dehydration process of the unclassified tailings non-cemented filling can be divided into three stages: rapid, steady and gentle flow zone. The steady flow zone is the key to improve dehydration efficiency.