Provided is a sealing structure of a soft infusion bag, the sealing structure comprising a connecting tube (2) and a sealing lid (3) matching the connecting tube (2), wherein a protrusion (20) is provided along an inner wall of the connecting tube (2)； an annular groove (30) matching the protrusion (20) is provided along the outer circumference of the sealing lid (3)； and the protrusion (20) can be embedded in the annular groove (30) to limit the movement of the sealing lid (3). Since the protrusion (20) is arranged in the connecting tube (2) and the annular groove (30) matching the protrusion (20) is arranged on the sealing lid (3), the sealing lid (3) is plugged inside the connecting tube (2) when mounted, such that the protrusion (20) in the connecting tube (2) is clipped into the annular groove (30) of the sealing lid (3), so as to enable the sealing lid (3) to seal the connecting tube (2), and thereby omitting the welding step and facilitating the operation and processing thereof. Further, during production, in comparison with plastic welding, with such a connecting method, the connection between the connecting tube (2) and the sealing lid (3) is greater in strength and is more stable, and the yield is higher. Moreover, the connection by way of mechanical cooperation has no need for welding, is energy-saving, and is not only environmentally friendly, but is also healthier for an operator.L'invention concerne une structure d'étanchéité d'une poche de perfusion souple, la structure d'étanchéité comprenant un tube de raccordement (2) et un couvercle d'étanchéité (3) correspondant au tube de raccordement (2), une saillie (20) étant disposée le long d'une paroi interne du tube de raccordement (2)； une rainure annulaire (30) correspondant à la saillie (20) est disposée le long de la circonférence externe du couvercle d'étanchéité (3)； et la saillie (20) peut être incorporée dans la rainure annulaire (30) pour limiter le mouvement du couvercle d'étanchéité (3). Comme
