According to this invention, a scanning probe microscope for scanning a surface of a sample with a probe by bringing the probe into contact with the surface of the sample, comprises a cantilever having the probe at its tip; a displacement detection unit to detect both a bending amount and a torsion amount of the cantilever; and a contact determination unit to determine a primary contact of the probe with the surface of the sample, based on the bending amount and the torsion amount detected by the displacement detection unit in all directions from an undeformed condition of the cantilever.