The emergence of 2D code technology is convenient for the public

but it become the hiding place of Trojans

viruses

etc because of its open production process. Such a two-dimensional code is scanned by the user once

it will spread the hazard to the scanner. However

the current two-dimensional code technology can not identify the source of two-dimensional code. Therefore

this paper analyzes the encoding mode and operational principle of QR code

summed up security risks of the current common two-dimensional code

and the QR code based on DHKE is presented. The experimental proof that the QR code based on DHKE can identify the source of two-dimensional code

effectively prevent users from scanning some illegal two-dimensional code

and improve the security of the two-dimensional code technology.