The present invention provides a packaging bag that is capable of effectively preventing a non-return spout nozzle from unintentionally being torn open or permanently deformed, a package that utilizes the packaging bag, and a manufacturing method for the packaging bag. This packaging bag comprises a flexible packaging bag body, which is created by means of fusing-bonding of a sealant layer of a packaging film equipped with a base film layer and the sealant layer, and a non-return spout nozzle, which is made of a thin flat laminated film having a sealant layer on both the front and back surfaces thereof and has a self-sealing function, and is constructed by fusion-bonding the base end section of the non-return spout nozzle to inner lateral surfaces of the packaging bag body with the non-return spout nozzle protruded sideways. A protrusion section that completely covers the non-return spout nozzle from the front and the back is provided continuously to the packaging bag body, a tear seam that runs across a middle section of the non-return spout nozzle is provided on the protrusion section, and the packaging bag body is left open either at the top or at the bottom.