Abstract: A heat-sealing device for liquid-filled tubes has a pair of openable pressing members 23, 24. One of the pressing members, 23, is provided in a pressing face 31 thereof with upper and lower two pressing pads 34, 35 extending in parallel to each other for pressing the tube T along and at respective opposite sides of each of the portions to be cut. The other pressing member 24 is provided in a pressing face 36 thereof with a U-shaped high-frequency coil 38 having upper and lower two straight portions 42, 43 extending in parallel to each other for heating the tube T along and at the respective sides of each portion to be cut. The pressing face 36 of the other pressing member 24 has upper and lower sealer portions 44, 45 each divided into a primary sealing portion 51, secondary sealing portion 52 and tertiary sealing portion 53.