There are around 24,000 existing bridges in Taiwan. These structures deteriorated and damaged due to the careless of maintenance and natural disasters. What is the remaining loading capacity and resistance to the earthquake, flood and typhoon of these deteriorated structures is recognized recently as an emerging subject and research area for bridge engineers all over the world. This paper presents the concept and procedures of developing a bridge health monitoring system (BHMS) currently executed in Taiwan. This BHMS is part of the National Bridge Management System (NBMS) of the country that has been developed and continuously maintained by the National Central University since 1999. Some real time bridge safety warning & monitoring systems have been established recently in the island. The difficulties related to the system design, sensing technology, data collection, transmission, interpretation, management and system maintenance that were admitted in the past are remarked.