We have developed a novel fiber-optic structural health monitoring system using fiber Bragg grating (FBG) sensors. This system enables not only to measure strain at fast speed over several kHz but also to detect acoustic emission and ultrasonic wave. Compared with conventional structural health monitoring system, this system has great advantage that sensory network can be quite simplified from the multifunctionality and multiplexibility of FBGs. The figure shows response signal of FBG sensor and conventional piezoelectric sensor in an ultrasonic damage detection test. As shown in the figure, FBG sensors have better damage detectability than conventional piezoelectric sensors.