In recent years, copper isotope can be measured precisely thanks to the improvement of analytical methods and the use of MC-ICPMS, and hence this field has become a new frontier in earth sciences. Copper isotope shows considerable variation in nature (from －3.03‰ to 5.74‰). This paper briefly describesand reviews the analytical methods and fractional mechanism of copper isotope. On the basis of data available, this paper focuses on the relationship between copper isotope composition and temperature, stages of mineralization and sources of ore-forming elements. As an important ore-forming element, copper exists widely in different geological systems and is active in ore_forming and rock-forming processes. Therefore, copper isotope may become a sensitive geochemical tracer and can play an important role in showing the sources of ore-forming elements as well as the ore-forming process and mechanism.