The invention discloses a method and a device for QR (quick response) two-dimension code position detection. The method comprises steps as follows: S1, obtaining a first image containing a target and a background of a QR two-dimension code; S2, performing binarization processing on the first image so as to obtain a second image only containing black pixel points and white pixel points; S3, scanning the second image to acquire a position detection graph; S4, judging the position relation of center points of the position detection graph and forming an isosceles right triangle; S5, positioning the QR two-dimension code. According to the method and the device, the operation is simple and convenient, the precision is high, a large quantity of judgment operations caused by interference of a non-target graph are reduced, the efficiency is improved, and complicated algorithms are avoided.