The gene encoding pannexin is a new gap junction family member discovered in 2000. Recent studies indicated that pannexin protein can form hemichannel on the membrane or intercellular gap junction channel, which is involved in many physiological and pathological activities. Here, we make a review of the latest research progress on the expression and cellular localization, the channel properties and the research methods of pannexins in an attempt to provide some evidences and methodological references to further investigation on the physiological and pathological functions of pannexin.