The invention provides a method for detecting position alignment offset and a printed circuit board (PCB) in manufacture process. The method includes: transferring a first picture including a reference scale to a metal layer on one face of the PCB in manufacture process, transferring a second picture including a measuring scale to a metal layer on the other face of the PCB in manufacture process, transferring the second picture in the way that the original point of the measuring scale is aligned with the original point of the reference scale, overlapping the reference scale with the measuring scale with length of N scales of the reference scale equal to length of N-1 scales of the measuring scale, etching the metal layers of the PCB in manufacture process and utilizing the reference scale and the measuring scale to measure picture transfer offset quantity. By means of the method, the reference scale and the measuring scale of the metal layers on two sides of the etched PCB in manufacture process can be utilized to measure offset which is the position alignment offset on an exposure machine, so that the position alignment offset of the exposure machine can be accurately detected.