In order to explore the effects of drag and configuration for twine diameter and catch on the trawl codend, different codend models with three twine diameters (1.11 mm, 0.96 mm, 0.54 mm) and two catch status (empty codends and codends with catch)under five current speeds (0.5 m/s, 0.6 m/s, 0.7 m/s, 0.8 m/s, 0.9 m/s) were carried outfor model test to compare and analyze the changes of configuration, drag and the horizontal hanging ratio of codends in the flume tank of Shanghai Ocean University. The results show that:(1) For empty codends, the drag coefficient of codend increases with the increase of twine diameter. With the increase of Reynold number, the drag coefficient decreases. (2) There is a positive correlation between codend resistance and flow velocity, twine diameter and catch. (3) The middle width of codend with catch increases with the increase of twine diameter. Compared with empty codends, the length of codends with catch increases obviously with the increase of flow velocity. While the overall configuration of empty codends is full. (4) The horizontal hanging ratio of empty codends decreases first and then tends to be stable, while the horizontal hanging ratio of codends with catch decreases first and then increases to the maximum. The results of this study can provide scientific basis for improving the hydrodynamic performance of mid-water trawl codend and the operation characteristics and selectivity of fishing gear.