Abstract: Cased hole directional window cutting drilling is a special drilling technology. It not only could make the "dead well" reproduce, but also could directly use the existing surface installations, reducing the cost of exploitation greatly. Satisfactory results have been reached by substituting imported CBL logging tool of DDL series with home made cement bond logging tool SJC-2C. This paper introduces the principle and characteristics of cement bond logging tool SJC-2C. Some comments on its application effects are also present.