Viruses have been classified into enveloped and non-enveloped subtypes according to their surface structures. The membrane proteins of the enveloped viruses are involved in the attachment, penetration, ncoating,
replication, and release of the viruses. The special membrane proteins are essential for the membrane fusion bywhich the enveloped viruses penetrate into host cells. Furthermore, structural data showthat class I and class II viral fusion proteins utilize a similar principle in membrane fusion. In addition, there are some viral membrane proteins, such as M2 of the influenza virus, Vpu of the human immunodeficiency virus type 1 ( HIV-1) , 3a of the severe acute respiratory syndrome coronavirus ( SARS-CoV) , among others, that have ion channel functions. The processes involved in viral membrane fusion and ion channel function provide newinsights into therapeutic design and proteins as potential targets of antivirals. Here we give three typical viral membrane fusion proteins as examples to reviewthe mechanisms of viral membrane fusion and viral ion channel function and the strategies of antiviral drug design.