To prevent the observation position of a sample from moving from a light axis regardless of inclination on two axes.

A sample stage comprises a stage body 17 that is arranged at the passage of charged particle beams along a Z axis in three axes X, Y and Z that orthogonally cross one another and has a spherical outer periphery surface 17b, and a stage body support member 18 for supporting the stage body 17 so that it can be rotated and adjusted around X and Y axes while the center of its spherical outer periphery surface 17b is arranged at the intersection point of the three axes. Then, the sample stage has a holder fitting groove 42a that is fitted to a section H1 fitted in a sample holder H when the sample holder H approaches from a holder attaching/detaching direction nearly in parallel with an XY plane, and a holder retaining member 42 for detachably retaining the sample holder H. Further, the sample stage is supported by the stage body 17, and has a retention material moving apparatus HM for supporting the holder retaining member 42 so that it can be moved and adjusted in the XY plane.