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.本發明係提供一種高品質的醫療用軟質容器。其係於可撓性袋構件(20)的外面，以形成有可插入手指之貫通路徑(45a、45b)的方式，使該中央部鬆弛而設置有一對的開關操作部(40a、40b)。一對之開關操作部的至少一方的上側及下側之至少一側的端部(42a、42b、43a、43b)係藉由熱封而被固定於可撓性袋構件的外面。藉由熱封固定至少一側的端部時的加熱區域(52a、52b、53a、53b)含有至少一側的端部的末端緣全部。於加熱區域之外周緣與開關操作部之側邊緣的交點，外周緣朝開關操作部之長度方向傾斜。藉此，於液狀物之注入作業時，於使開口部較大地開口之狀態下，可穩定地握持該醫療用軟質容器，又，難以產生應力集中。
