Providing a packaging machine and a sealing method in the packaging machine both of which can reliably seal a packaging bag in a good-looking finish without forming large bubbles on a seal inner surface of a bag mouth of the packaging bag and/or creases on a seal part.A packaging machine includes a seal part preheating station for preheating a seal part of a packaging bag after the packaging bag has been filled with an article and steam deaeration has been carried out, a decorative seal applying station provided downstream of the seal part preheating station for applying a decorative seal to a part of the packaging bag above the seal part and an ultrasonic seal applying station provided downstream of the decorative seal applying station for applying an ultrasonic seal to a part of the packaging bag A below the seal part.