Taking Longjing tea as the object, aiming at the deficiency of current Longjing tea packaging in the transmission of product information, the promotion of tea culture and the abandonment of packaging after purchase, this paper ains to probes into the design and application of AR technology in Longjing tea packaging. Auto CAD was used to design the packaging structure of Longjing tea which can be reused into handicrafts; according to the display characteristics of Longjing tea, the packaging decoration drawing with AR technology; was designed the video of brewing and brewing, etc. of Longjing tea was edited; a three-dimensional model of tea culture was created; Unity, Vuforia and visual studio tools was used to develop application software that can realize the combination of virtual and real effect. A mobile application software for Longjing tea packaging was released, which identified Longjing tea packaging box by means of AR image recognition and 3D scanning, and realized the functions of tea model de-card, rotation and scaling, as well as the display effect of Longjing tea production technology and producing area information. With the application of AR technology in Longjing tea packaging, the display of product information is changed from flat to three-dimensional; The secondary use of packaging as household furnishings reduces the waste of resources. The combination of traditional products and modern technology realizes the "visualization" of "tea culture" and provides a new idea for the promotion of traditional culture.