Grains are widely present in industrial productions and processing, and are stored in silos. In the silo, auxiliary structures are added to achieve efficient production. However, little effort has been devoted to the influence of the internal structure of the silo on the granular flow. In this work, a silo with a central decompression tube is studied through experimental measurements and discrete element methods. Then, the influences of the central decompression tube on the flow behavior of grains and wall pressure are analyzed. Results show that the grains are in mass flow in the silo without a central decompression tube, while the grains are in funnel flow in the silo with a central decompression tube. Moreover, regardless of whether there is a central decompression tube in the silo, the maximum pressure appears at the top of the conical silo. In the lower part of the silo, the wall pressure of the silo with a central decompression tube is lower than that of the silo without a central decompression tube. Therefore, a silo with a central decompression tube is more conducive to grain storage and discharge than a silo without a central decompression tube.