Objective To compare the sensitivity of methods for detecting H5N1 influenza virus． Methods The H5N1 influenza virus was amplified and quantified by plaque technology． Then the virus was diluted to compare the minimal titer using methods of cell inoculation，hemagglutinin，RT-PCR and Real-time PCR． Results The minimal titer detected using the methods of cell inoculation，hemagglutinin，RT-PCR and Real-time PCR were 10 PFU /mL，10 PFU /mL，103 PFU /mL and 3. 52 × 105 PFU /mL seperately． Conclusions We found that the methods of cell inoculation and real-time RT-PCR were the most sensitive methods; while the hemagglutinin method was timesaving，it showed low sensitivity which need to be identified in future; RT-PCR method was timesaving，in addition，it also showed high sensitivity．