Abstract: Starting from related concepts, the author pointed out differences between earthquake prediction, forecasting and pre-caution, furthermore, pre-caution is prompt alert after made after an earthquake instead of any prediction or forecasting made before. Theoretical principle of earthquake pre-caution is based on wave velocity difference, typical earthquake pre-caution system such as Mexico city’s Seismic Alarm System(SAS), Japan’s Earthquake Pre-caution System(EEW) and Urgent Earthquake Detection and Alarm System(UrEDAS), California’s Earthquake Alarm System (ElarmS), Taiwan’s Earthquake Quick Reporting system and so on, have been widely applied in earthquake prevention and disaster reduction, as well as for significant projects (such as dams, nuclear power plants). Despite of all, Earthquake pre-caution system is still in its early stage, certain imperfections are unavoidable such as false warning and delayed warning, whereas potential benefits remains in practical use and it has already effectively solved some problems. After the devastating 5.12 Wenchuan Earthquake, China is ready to set up similar earthquake pre-caution system. Based on its feature and practical national situation, this paper has probed into construction issues from certain aspects including fundamental faulting research, seismic monitoring network as well as information publishing.