To provide a cutting blade for a bag making apparatus, the bag making apparatus, a method for producing a packaging bag by means of the bag making apparatus wherein easily opening properties can be obtained regardless of size of the bag and productivity can be improved.

A cutting blade 5 for a bag making apparatus is constituted by comprising teeth 5A for cutting formed along the cutting direction of a packaging bag and teeth 5B for notching being intersecting at right angles to the cutting direction and formed by pinching the tooth 5A for cutting and on both sides thereof. Therefore, as a packaging bag is cut by means of the teeth 5A and at the same time, notches can be accurately formed without deviation of a film to one side when the notches are given, easily opening properties can be obtained.