A network application performance measuring method which supports the application of high bandwidth real-time video of internet belongs to the technical field of bidirectional transmission performance measurement of IPv4/IPv6 internet. The invention is characterized in that a random data flow which simulates the virtual real-time video or virtual real-time video data flow is adopted as a ''probe'', a network which combines a user application system with a measuring server and is based on an active mode and a reflection mode and an application performance measuring method thereof, a network which combines the client system with the measuring server and is based on the reflection mode and the application performance measuring method thereof, and the invention has the functions of subscriberidentification and DOS attack prevention. The invention effectively realizes the intercommunication of the network measuring method which supports the application of high bandwidth real-time video and the application system. The description languages of the video application subscriber, the application system engineer and the network engineer to the network problem are unified. A real-time automatic and independent measuring environment is established. The criterion is provided for quickly finding out the bandwidth bottleneck of network transmission for diagnosing the failure and settling theproblem.