An instrument for direct measurement of the adhesion forces in the ultrahigh vacuum (UHV) chamber of surface analysis apparatus [Auger electron spectroscopy (AES), x-ray photoelectron spectroscopy, low-energy electron diffraction, etc.] was developed. It is attachable to any UHV chamber which has a open flange, a manipulator, and a specimen introduction system. It was attached to an AES apparatus (Perkin-Elmer PHI model 650) and tested. The adhesion force between the Au ball and Si wafers was examined.