A bipolar electrosurgical instrument has a handle and an operation tool. The operation tool is mounted on a front end of the handle and has multiple holes densely formed in and spread over at least one working surface of the operation tool. With the multiple holes formed on the at least one working surface of the operation tool, tissues of a surgical site can be heated uniformly and adhesion of the surgical site is minimized. Moreover, since the multiple holes are directly formed on the at least one working surface, the multiple holes do not become shallow under long-term use and no toxic gas would be released when the operation tool is heated to high temperature. Accordingly, anti-adhesion effect of the operation tool and health of medical staffs can be assured.