The invention relates to the technical field of machining, in particular to a CCD (Charge Coupled Device) vision alignment algorithm applied to robot patching. A CCD calibration algorithm comprises the following steps: A) obtaining a relationship between a first CCD coordinate system and a robot base coordinate system; B) obtaining the relationship between a second CCD coordinate system and the robot base coordinate system; and C) through the XY axis translation operation and the U axis rotation operation of a robot, obtaining a coordinate, which is relative to a current U axis rotation center, of the original point of the second CCD center coordinate system to finish CCD calibration. An alignment calculation algorithm comprises the following steps: D) attracting a first workpiece to the second CCD to carry out detection by the robot, and obtaining a first coordinate position of the robot; E) causing the robot to operate above a second workpiece, and detecting and obtaining a second coordinate position of the robot by the first CCD; and F) through the first coordinate position and the second coordinate position, calculating the coordinate of the robot during patch alignment, and finishing the patch alignment. Alignment accuracy can be improved.