Because pandemic influenza virus infection can result in large-scale human death and have a major economic impact, influenza virus is one of the most important microbial pathogens. To control influenza virus, both clarification of the mechanisms by which the virus causes disease and the development of effective drugs and other therapies based on these mechanisms are needed. Virus infection often induces cell death, which can play an important role in disease pathogenesis, and influenza virus, in particular, has been shown to induce significant levels of apoptosis in vivo and in vitro. Over the past decade, the mechanisms by which viral and cellular factors modulate apoptosis induction in influenza virus-infected cells have been revealed. Viral proteins such as hemagglutinin, neuraminidase, M1, NS1, and PB1-F2 have been shown to be involved in apoptosis induction through extrinsic or intrinsic apoptotic pathways. On the other hand, several drugs with different mechanisms of action and a neutralizing monoclonal antibody (mAb) are currently used to control influenza virus. A better understanding of both how influenza virus infects host cells and the intracellular signaling pathways that are activated by infection is essential for the development of antiviral drugs and other effective therapies.