Abstract: Disclosed herein are a straw and its manufacturing method. The straw contains an inner tube, an outer tube and a barrier layer. The inner tube has a first port, a second port and a hallow part at the inner side of the inner tube. The hallow part connects the first port and the second port. The outer tube disposed outside the inner tube has a first port and a second port. The first port of the outer tube is cut flush with the first port of the inner tube. The barrier layer is sandwiched between the inner tube and the outer tube, and the barrier layer can block the penetration of gas between the inner tube and the outer tube. Furthermore, a flexible container having the above-mentioned straw is also disclosed herein.