In the disclosed flexible container for medical use, a pair of opening/closing operation sections (40a, 40b) are provided to the outer surface of a flexible bag member (20) by loosening the center section thereof in a manner so that insertion paths (45a, 45b) into which a finger can be inserted are formed. At least one of either the upper and lower end (42a, 42b, 43a, 43b) of at least one of the pair of opening/closing operation sections is affixed to the outer surface of the flexible bag member by means of heat sealing. The heated region (52a, 52b, 53a, 53b) when affixing the at least one end by means of heat sealing includes all of the terminal edge of the at least one end. At the points of intersection between the outer edge of the heated region and the lateral edges of the opening/closing operation section, the outer edge is oblique with respect to the lengthwise direction of the opening/closing operation section. As a result, it is possible to provide a high-quality flexible container for medical use that resists concentration of stress and that can be stably maintained in a state wherein an aperture is widely opened when performing the task of injecting a liquid material.La présente invention concerne un récipient flexible décrit pour utilisation médicale dans lequel une paire de sections opérationnelles douverture / fermeture (40a, 40b) sont disposées sur la surface extérieure dun élément de poche flexible (20) en relâchant la section centrale de celui-ci de telle manière que des chemins dinsertion (45a, 45b) dans lesquels un doigt peut être inséré soient formés. Au moins lune des extrémités supérieure et inférieure (42a, 42b, 43a, 43b) dau moins lune de la paire de sections opérationnelles douverture/fermeture est fixée à la surface extérieure de lélément de poche flexible au moyen du thermoscellage. La région chauffée (52a, 52b, 53a, 53b) lors de la fixation de lau moins une extrémité au moyen du thermoscellage comprend tout le bord terminal de lau moins un
