Abstract: Objective This study was conducted to analyze the links related to the detection of infectious diseases under the mode of internet - based reporting for providing data for the implementation of early warning of outbreaks of infectious diseases. Methods The data on all thecases of measles reported in March, 2006 were analyzed using the SPSS10.0 statistical analysis software to find out the time intervals of the links from onset of the epidemic to its diagnosis, from the diagnosis to filling the reporting cards, from filling the reporting cards to the reporting, and from the reporting to the check by China CDC, and the problems occurring in the process. Results The qualityof the reporting of infectious diseases by the medical facilities and the CDCs all over China wasimproved to a certain extent in 2006, compared with that in 2005, but there still existed unpromptness in the filling, reporting and checking of the cards, far from the requirements of an efficient earlywarning of infectious diseases. Conclusion Medical facilities have an important role to play in the surveillance of infectious diseases. In terms of the importance attached to the responsibility, there wasgreat difference among the individual facilities over the country, which should be taken seriously.Constant inspection and supervision of the facilities that lag behind in the work are supposed to bereinforced, with the procedure for the reporting of the epidemic standardized.