To provide a packet transmission method and a packet transmission system which avoid the packet loss in transmitting data packets over a network.

A video camera 1 or a video deck 2 outputs analog image data at a transfer rate of 6 Mbps, and an encoder 11a encodes video frames F1, F2, etc. of the analog image data into digital data based on the MPEG-2 standard. Every time acquiring the encoded video frames F1, F2, etc., a packet generator 11b forms four of them into a packet and intermittently sends a series of groups of packets p1-p4, p5-p8, etc. at a transfer rate of 6 Mbps, and a packet sending time controller 15 temporarily stores the groups of packets p1-p4, p5-p8, etc. obtained from the packet generator 11b in a buffer memory 15a and sends the stored packets individually such as packets p1, p2, etc. at a time interval t based on the transfer rate of 6 Mbps.