Mixed reality (MR) is the technology which merges real and virtual worlds in real-time. In MR space, a real object can be changed its visual appearance by superimposing a CG image (CGI) on it. We confirmed that the presence of center-of-gravity (COG) can be changed by MR visual stimulation in our previous work. And we named this illusion the "Shape-COG Illusion". In this paper, we verify effects of superimposing virtual object of a pole on a real pole. We measured the perceived COG of 180 combinations of real objects and virtual objects. We analyzed relationship between COG of real/virtual objects and perceived COG