The 2 dimension code is hard to keep secret, introduced an image cryptography technology for military internet of things. Adopt visual cryptography method, and transmit traditional QR code image to create 2 pixels random distribution share images. Through exclusive disjunction of 2 share image matrix value, use Hamming weight w of image pixels matrix to judge QR code primitive image judge black and white value, create original QR code image, then the QR code can be reverted and read in authorization equipment. The analysis results shows that the method can overcomes the security shortages of traditional QR code scanning technology, the cryptography QR code image can be resumed well with better security in military internet of things.