A medical procedure called Interventional Radiology(IR) is paid much attention in recent years. IR can be performed percutaneously while a doctor observes patient's fluoroscopic image. Therefore this surgical method is low-invasiveness method. In this surgery, computed tomography (CT) equipment is often used. But a doctor is exposed to strong radiation from CT. Thus, we have developed a remote-controlled surgery support robot called 'Zerobot'. Because Zerobot is placed front of CT equipment by human, an angle offset from installation target position occurs. If a doctor punctures without noticing that Zerobot has an installation angle offset, there is danger of hurting the part that should not be hurt around a target cancer. In order to solve this problem, we propose an angle offset compensation method and the installation angle offset derivation method using a CT equipment is proposed. Then, effectiveness of proposed method is confirmed through experiments.