Automatic time service intelligence wrist -watch of SOS based on big dipper generation satellite navigation system, it includes treater, baseband, radio frequency circuit, power amplifier, low -noise amplifier, receiving antenna, emit antenna, display screen, SOS button and power module, emit antenna loops through power amplifier, radio frequency circuit and baseband connect the processor, and receiving antenna loops through low -noise amplifier, radio frequency circuit and baseband connect the processor, display screen connect the processor, power module is used for the power supply to give intelligent wrist -watch. The utility model discloses need not to rely on the public network and also can realize the time service of intelligent wrist -watch, location and a key SOS function, also can use this intelligent wrist -watch in public network unlapped remote region.