The invention discloses a method and a device for large-range and high-resolution atomic force micro detection for a large sample. By adopting a method combining the scanning of a piezoelectric ceramic probe and the large-range motion of a step motor and designing an open sample stage, the micro-nano detection of large-sized super-precise workpieces is realized. The device is provided with a large-range and high-resolution scanning probe system, an X-Y-axis step electric translation stage, an optical platform and a scan imaging and feedback control system, wherein the large-range and high-resolution scanning probe system consists of a laser, a light path tracking lens, piezoelectric ceramics, a micro cantilever probe and a photoelectric detection element; and the X-Y-axis step electric translation stage is used for moving large-sized samples in large range. The method and the device have the advantages of overcoming the limitation that a conventional AFM is only suitable for small-range detection of small samples, designing a simple and practical lens system to solve the light path tracking problem when the probe scans in the large range, and adopting the open sample stage and the two-dimensional step motor to realize large-range scanning and detection in any area for the large-sized super-precise workpiece samples under the condition of keeping the ultra-high resolution of the AFM.