To provide a soft bag, facilitating putting in and out of an object to be stored, and easily making an opening part comparatively widely open especially at the side part.

This soft bag has the opening part H, in which the upper end parts of the front and rear face parts 1, 2 are freely opened and closed by a fastener 3 between both left and right side parts. In either one or both of the right and left side parts, a spring member is disposed with one end thereof located on the front face part 1 side, and with the other end located on the rear face part 2 side, whereby the opening part H is energized to be opened in the longitudinal direction.